Wish I could help you out, but I have no experience with valves, camshafts, lifters, pistons. 

Rotaries are so much simpler... :)  Good luck with your search.

Actually, try giving Arie Nol's a call and ask who they would send this type of work to.  They seem to be a decent repair shop, and have provided free advice in the past.  http://www.arienol.com/