Quick question about parts for fuel cell

I am getting a new aluminum fuel cell fabricated for my 32 Bantam altered. I am looking for a company that sells an aluminum filler tube and cap that can be welded into the new tank. I could have them cut out the filler cap assembly on my existing cell but would rather they were able to build the new one before having to take my existing out of service.

Any suggestions?

 

caps

earls makes them as well as the chassis shop http://secure.chassisshop.com/partlist/6049/

 

S&W sells them.....i hope this link works.
http://www.swracecars.com/Files/pdf/CATpg58.pdf
Darren