B-Square makes a rather clunky looking one piece base cut for Weaver rings. Look at it here:
http://www.brownells.com/aspx/ns/store/ProductDetail.aspx?p=1764&title=RIFLE+BASES
Two piece here:
http://www.brownells.com/aspx/ns/store/ProductDetail.aspx?p=18865&title=TOP+MOUNT+BAS ES+-+KIMBER-MAUSER
Considering what rings cost, I would go with Leopold base. Much better looking the Weaver style, IMO.
I also suggest not cutting on a straight military rifle, drill and tap only on a rifle that is already cutup.