MGB: Expansion Tank...source?

I want to put an expansion tank on my cooling system, anyone one have an after market source. 74 MGB CB.

Don - Instead of going to the expense of an external expansion tank, consider a coolant recovery system. See the article, Expansion Tanks, Coolant Recovery Systems, and How the Cooling System Works in the Other Tech Articles on my web site at: http://homepages.donobi.net/sufuelpumps/
Cheers,

Dave, this is what I was looking for...I had the wrong terminology, thanks for the info. I will make my own based on your great info. Thanks again.