Just curious... is the car posted on Craigslist locally? If you truly want to sell it, posting on CL is free, takes only a few minutes and will get you significantly more traffic than you're probably seeing on it now; especially if you throw in a few tags for cars in the same class (Subaru Legacy GT, ect) and point out that it's both sporty, practical and AWD. Maybe even posting it on Cars.com or Autotrader might not be a bad idea. Sure, you'll get a few calls/emails from nimrods from time to time, but you're also more likely to attract a real prospective buyer. Certainly not a bad idea to update the original post with your current asking price as well.
Also, since you have a larger turbo with the normal bolt-ons added to it (sans downpipe), you might want to mention something about the car actually being tuned specifically for your setup... and if it's not, well, that's certainly something you should look into. I've been buying, selling and modifying years for going on ~15 years now and I know for a person like myself, seeing someone running a larger turbo without it actually being tuned for it would scare me away in a heartbeat. I get your argument of "some buyers might prefer the ECU to be stock" that was made previously, but the reality is, the car already has a Cobb AP, so the ECU isn't stock anyway; and for a modified car, I think people would rather see that you've had the car legitimately tuned so they don't have to worry about another motor popping on them.
I know if I was looking for another Miata, I would prefer to buy a stock version, but, if a person had modified the car, I would feel much more comfortable if I saw words like "professionally tuned by [insert name here] at Flyin' Miata". It would lead me to believe that the engine management system was legitimately tuned for that specific car and had a safe tune on it. With the mention of the car already having blown a motor, I would certainly want to know that if a bad tune caused the problem, that the problem had been rectified by a safe, solid, consistent tune (preferably not an OTS/canned tune, but some people would be ok with even an OTS map for a specific setup)
Otherwise, I think you would probably sell the car faster if you just sold the aftermarket parts and put it back to stock. At that point, you could still have a reasonable asking price (most people will pay more for a stock vehicle anyway) and you could sell your aftermarket parts to recoup at least a decent chunk of your investment.
It might not even be a bad idea to list your reasoning for selling, in order to explain to someone else that it's not just a car that you blew a motor on and are now desperate to get away from. Common reasons why people sell a "modified car":
-Family is growing and we've decided to get something bigger (i.e. SUV, ect).
-Bought another new car and don't have room in the garage for it anymore.
-"I love the car", but financial hardship has forced me to part with it.
-Kids are going to college and need to help them pay for it (or even- I can now get that 2-seat convertible I always wanted!)
-I don't get to drive it much anymore (hard to argue with a practical, 4-door, AWD vehicle that gets half-decent gas mileage haha!)
-My wife can't drive a manual. (<-----Kind of a cop-out, but legitimate)
-Want something that is better in the snow (again, hard to argue with an AWD sedan!)
-I'm moving and can only take 1 car with me.
Most people don't want to buy someone else's headache. Saying that "I want something better", doesn't inspire a whole lot of confidence. Especially when said vehicle has already suffered a blown motor and the seller is trying to unload shortly after replacing the motor with no explanation as to why the motor was blown and what preventative measures have been taken to ensure said motor does not blow again.
Truth is, if you really just have your eye on something "better" per se, you can always just trade the car in. Sure, you can sell it for a bit more private party, but trading in does have a few advantages:
-Not having to find a buyer for your current vehicle.
-Only having to pay taxes on the difference between the two vehicles! In other words, if you're buying a $30k car and the dealer is giving you $15k for your trade-in, you only have to pay taxes on the $15k between the 2 cars. Sometimes this is enough to make up the difference between the private party and trade-in prices. I.e. dealer is going to give you $1500 less than you can sell the car for, but in return, you save yourself from paying $1500 in taxes to the state of Colorado's DMV. At that point it's pretty much a break even situation IMO.
To be honest, I'm not trying to come off as a jerk whatsoever. I'm a former MS6 owner that has went through the buying, modding and selling game more times than I care to admit and am just trying to give you a few tips that I've picked up over the years. I'm just trying to help you sell the car.
Good luck either way!
-Brandon