I would even bother getting an external wastegated turbo if you're gonna run low boost. The Garrett internal wastegated turbos are pretty decent. A 16G would be more than enough to have you in the 300hp territory if you wanted to and they're cheap new - under $550
A .48 A/R turbine housing will spool super fast but will choke up top.
Also look at this spreadsheet to help you size your turbo:
http://www.squirrelpf.com/site/index.php?page=Turbo+Sizing
