Hi Brian,
My fave cold - pack is Futuro re-usable cold-hot pack.
They're soft and squidgy, even after being frozen, so they mould to any body part....Oh that sounds a bit rude!
I've used them for hot and cold therapy and I've had mine for literally YEARS. Just remember to wrap it in a teatowel.
The other good thing about these packs is they're Made In Australia. So your money will stay here.
I've just bought my Father-In-Law a couple, because he's just had a knee replacement and he loves them.
P.S. His name is Brian too! Spooky
All the best for you hip replacement. Sending you good vibes from the left side of the country...
Noong