I don't know what the going price for PIS are but I got this in an email and thought I would pass on the information. They also have some very nice nursing clothing.
http://www.mommygear.com/breastpumps.htm

Laurie~Craig's wife~Mom to 4 blessings nurtured at the breast CJ(24)Travis(21)Beka~adopted(9)Rab(6)