Any turbo ship will be ablt to port it for you, you may also want to do a 5-10 degree clip for more top end, it won't sacrifice too much low end since the turbo is so small anyways.
The only real upgrade is to a t-28, which doesn't really support alot more hp. You can however up to a big t28 (http://www.forcedperformance.n...8.htm)which will start giving you some real power.
Any reputable turbo shop worth it's salt will be able to port your turbo and clip the wheel. I recommend Forced Performance (
http://www.forcedperformance.net/) I have worked with them when I used to have my DSM and they were great.