turbo inquiry

[BKLYN2FLORIDA]

im looking to buy this turbo from a private seller, i believe its a 60-1 (rebuilt), under 100 miles, never got to race it, has a billet rear plate.
questions:
how much is it worth, max i should pay for it.
im installing it with the engine listed below with a recent rebuilt tranny with pro-torque converter.
any n all input is appreciated

pictures in this link
turbo pics pictures by irv167 - Photobucket

 

[artrenee10]

500 shipped w/paypal fees included is a pretty good deal...