Sounds like a small turbo with ball bearings is what you are looking for the blouch 0.5r dominator ball bearing turbo would most likely suit your needs well, but it is an STI style turbo, so you would need either a FMIC which would lose you a bit of spool, or a custom TMIC to be able to utilize it. If you contact blouch about it, they might be able to make it with an LGT style housing so you can retain your tmic.
Borg Warner is supposed to be making some extremely fast spooling turbos for our cars with dual ceramic ball bearings and a titanium wheel as well. There are a couple of catches though, due to the design of the turbo, you would need to also purchase their dp and exhaust manifold b/c these turbos wont hook up to yours. Also as far as I've heard people have ordered these turbos a year ago and nobody has gotten one yet. I might be wrong about that but I havent checked on those setups in about a month.
GL with your situation.
p.s. Have you considered buying a couple of drums of e85 to keep in your yard, Ive heard that it runs great at altitude.