has the 3800 Series II, no supercharger. has 193,000 miles, how tough is it to find a Supercharger in a junkyard that is good? I know you can find plenty of Park Aves, but how many supercharged ones might there be.
how much HP and Tq would there be after that
is this a good idea?
eBay Motors: GM 3800 supercharger/ blower (item 260281849737 end time Sep-07-08 18:09:17 PDT)
I want to get this for my buddy as a birthday gift (I get all my friends car parts as gifts, if they have cars)
how durable is this motor, as in how many miles do they normally last?

You can't just slap a supercharger on a 3800. There are several differences.

I thought that would be the case, what are the differences?

Besides the PCM? The SC 3800 is a much more robust engine with heavy duty parts, I believe the cam is different, I seem to remember the connecting rods as well.

Darn, well, no big deal, other than the crappy fiberglass roof, it is a solid car, and ULTRA QUIET, he probably wouldn't want to change that anyway, but it would've been cool