No one to my knowledge has opened up their engine on an N/A maxima. Only the FI guys on this board have.
Cattman doesn't make cams, they sell them. JWT is the company who makes them. $1200 is for 4 cams. You aren't going to find any cheaper, unless you send some cores to ISKY, Crower, Schneider, etc.
No one really knows what sort of gains they get on an N/A car because no one has them on an N/A car. I've been meaning to call JWT because I'm sure they've tested them on an N/A car at some point in their development.
Lots of us have the variable intake.
There are 2 turbo kits out for the maxima, check out the Turbo/Supercharged forum.
The stillen SC is the only SC out. Changing the boost is as simple as changing the pulley. Then you'll need more fuel of course. Check the turbo/SC forum.