Hey Amigo,
I asked this same basic question a few months back. I didnt find any distributor for Uberti original replacement grips so I ordered some from Teepee Creeper at Western wildlife wonders and they are priced right and pretty decent quality. I am sure others have them as good or better but wish you luck if you insist on factory grips. You could get lucky and find someone who replaced the originals with something else preferred like stag. Good luck, RC