I'd see if an offer of Lee, Alfonzo, Varitek and Vasquez would get you another starter (Odalis Perez?), a backup OF, and an upgrade at catcher. I would think that might pique a few owners interest, I know it would mine. Then, if you can pull off a 3-for-4 deal, pick up Phelps. The thinking here being that he projects out to a 30+ homer and 110+ RBI guy from his numbers last year. There's also an outside chance that he may at some point be eligible at catcher, which would be a huge advantage.
If you can't find a deal that works for you, try offering around Foulke and Guardado. You don't have to trade both, but see what one of them and Alfonzo will get you. My philosophy on saves is that if you can get a decent closer in the later rounds of the draft, do it, but don't draft one before the 10th round. I feel that there are always closers who no one expected to close that will pop up throughout the season. Last year I didn't draft one closer on any of my teams, and I finished first in two and second in the other. I picked up Mike DeJean, Scott Stewart and Jorge Julio in each league and did fine on saves. I always keep my eyes open for guys like that.