As far as the RB engine, the C12 that Zandor recomended is a nice engine. What I would recomend, for a few extra bucks is the V12 3port. I have it on my NTC3 right now and even after 4-5 gallons, it is still a great performer. Compression is superb and it still kicks butt. Only differences between the C12 and V12 is that the V12 is a nonpull engine BUT it is rated at a higher power rating (more stars since RB doesn't publish HP numbers).
Sorry I can't help you with the foams since I am in need of about 20 sets of 4 myself. If you tell me what shores you are looking in to and the size, I can find out at my LHS for you. I usually fet Ellegi's for about $14/pair (both 26 and 30 mm). Let me know and I'll find out for you.