I think 2500 is about right for a GSR motor with that many miles, if i were you I would save up a little more and go with a JDM motor, 90% of them have less than 30k on it and it will have an LSD and higher compression from the get go. I wouldn't pay 1500 for a B18c, i would think something is wrong with it. sounds too good to be true.
Milan