I picked up an upgraded turbo for the Volvo. It is a Mitsubishi 16T turbo out of a 1998 Volvo S70 T5 vs the turbo in the car is a Mitsubishi 13G. This is a direct swap wish no modification at all. I will end up with 10psi vs 7psi and a better top end. I'm also swapping the ECUs.

The turbo I picked up is out of the pull and pay and I'm not sure the mileage.

What is acceptable shaft play?
Should I replace the O-rings?

I would really lean towards rebuilding it since it is already out of the car. Who knows whats been through it! But on the other hand they can be had for so cheap you can probably pick up another used one for cheaper than the rebuild kit! I think TD04 kits are like ~$60

I will probably just rebuild it myself. It seems like kits vary in price form $50 to $150. The rebuilt turbos I've seen run between $350-$700 for this application.

Do you know of any kits that are quality but not crazy expensive?
Are there any companies in Colorado that can do the balancing?

Is there much wear (erosion) on the compressor wheel or the turbine? If they look good and nobody ran it without a filter causing blade damage then the balance should be fine. I'd put new seals and bearings in it and slap that pooch on there! If there is some question about blade damage, or if someone has clipped any of the blades then I'd send for balance. The turbine and shaft are a balanced unit and the compressor is balanced dynamically by itself so disassembly and re assembly should have no affect on balance.

There isn't any damage and shaft play is almost nonexistent. The car was wrecked which is always a good thing because it means that the car ran when it went to the junkyard. The car did also have silicon hoses on all the intercooler pipes as well.