Hi Quinton,
I would take your carburetor base to a machine shop and see if they can fix it for you. It may be possible to thread a new nipple into the base after the remains of the old one are cleaned up/out.
As for a good carburetor shop, I have good experience with this company:
Daytona Parts Company
386-427-7108
www.daytonaparts.commail@daytonaparts.com
This company assembles nearly all the carburetor kits sold by other suppliers. They have the largest archive of original carburetor blueprints from the original manufacturers in the world. They make kits for virtually every automotive carb made from 1900 to 1980.
They also do top quality rebuilding of carburetors for those who don't wish to do it themselves.
Ask for Ron Hewitt or Tim Hewitt.
Another member of this forum has recommended another company that he has had good luck with. I don't recall the name but it should be easy to find using the Search function above.
Any new developments with the harmonic balancer?