tfs stage 1 would be a good choice. Here is a link to one at a good deal. Just remember to do something about the stock valve springs and retainers. I would even consider taking the heads off, and having some work done on them. I've done a few sets of e-7s, and they turned out pretty well considering they're a stock head. I could probably do a set for you for a reasonable price.
http://streetcarforums.com/showthread.php?t=98961