I have two of the 105-3202 (2 5/8 Autometer pressure/electric gauge mounting cups) and one 105-3204 (2 5/8 Autometer mechanical temp gauge cup). These have been mounted in my Camaro for the last two years and are in excellent shape.
http://www.jegs.com/p/Auto-Meter/Auto-Mete...745207/10002/-1
$10 ea plus freight
I also have two 2 5/8 Autometer Ultra-lite gauges that came out of my car. Both have limited run time (a few hundred street miles, 50 minutes on a track and 50-ish autocross runs). One is an electric 300 degree oil temp gauge, pn 105-4447. The other is a mechanical oil pressure gauge, pn 105-4421.
http://www.jegs.com/p/Auto-Meter/Auto-Mete...745230/10002/-1
Oil temp $35 plus freight
Oil pressure $30 plus freight
Buy multiples, save on freight. I'll ship it all for actual cost and combined will be cheaper.