My s.o. and I were both given cryocuffs by our ortho surgeons. (Yeah,
we both have a bad habit of ripping up knees and one of our "bonding
moments" in courtship was to learn we had the same surgeon. *laugh*)
They are a bit cheaper than some of the other links I have seen.

http://www.cryocuff.com/

No electricity or pump (I know, I just foiled plans of converting it
into a mim-pond when done), just a thermos, tubing and the cuff. Mine
has gotten me through several surgeries with just tylenol and advil for
pain. I'm extremely sensitive to painkillers as I learned after my
first surgery. Warning, never run to the bathroom immediately after you
have had knee surgery, forgetting you're supposed to be on crutches.

Susan
shsimko[@]duke[.]edu