Hi Douglas.
My source for forged NiAlBr in 3/8" bar is:
Chrome Nickel Alloys Limited
The Barn, Manor Farm Barns
Baines Lane
Seaton, Rutland
LE15 9HP
www.cnalloys.co.uk
Andrew Clark is the MD and is very helpful. Mention my name when/if you contact him - I might get a discount next time!.
Yours aye,
Bill