How much should I be prepared to trade away to get a shut-down closer?

Question

..someone like Papelbon or Wilson from the Giants

Answer 1

those guys aren't even shut-down closers this year.

have you seen wilson's era?

if you want shut-down, target  

KROD

SORIA

LIDGE

Answer 2

It would be easier if we knew your roster, but as someone who has traded both Lidge and Soria this year, I would say expect to give up a #2 OF type. I got McLouth for one and Cano andWainwright for another.