OC'ing modules in 512mb denominations for opty 146

[amddude]

I am building a opty 146 system for a friend. I am trying to find him 1-2gb of something that will let him overclock decently (ultra-d is the board). I have 2gb of the 2-2-2-5 patriot xblk in my system which I like, I know it's TCCD. However, that goes for about $50 per 512. Is there anything that would overclock well but be in the $150 range?