I'd say that a straight, not rusted out GSR could be found for around $3500. It won't be the prettiest one out there, but it'll work.

Actually, I'll just go look at kbb.com.......

'94 2-door GSR, 175000 miles, private party sale:
Fair - $2450
Good - $2950
Excellent - $3350

Make the car a year newer, and it seems to add about $400-500/year.