Ron:
Might try Advanced Welding in Mt. View. They have been there working with the defense department (Moffett NAS) on various bits and pieces so I suspect they might be able to work on your stuff.
They repaired a hole I made in my Edelbrock cylinder head. They knew exactly what grade of aluminum to fill in my mistake.
http://www.advancedwelding.info/
Good luck!
-Herman