Dont waste your time with Greener's , they wont have any and will charge you an arm and a leg to make one .There is someone in the State's who does very good lost wax castings .I know Dixe Gun Works used to .I saw some that had been done for a hammer gun that was sent to the UK for sleeving a few years back. I'm sure that some one on this site will be able to supply you with their details.