You really don't wanna go the cheap route. If he's gonna do it, do it right. For the most part, you're going to get what you pay for. I've seen tons of people get cheap kits only to have the manifold end up cracking, shit not fit right, and I've even heard of turbo's cracking into two pieces.
Some turbo's that you should consider are the T25, GT28R, or the GT32. What are his power goals? Budget? Is he going to be upgrading any internal engine components?
If you're looking for a shop to help you pick out parts, complete the install, and tune, I highly recommend you check out www.slowmotionmotorsports.com.