They were used from 1937 to 1960 at least. Cat part number 3B8830. Is there any one reproducing them or have they been able to source them from Bosch (Ensign). 

ACMOC chapter 19 have them for sale - www.acmoc.org/chapters/nineteen
 

Florin also has a bunch of them

Cat was selling bowls a year or so ago, not sure about the assembly. But for 20 years the Cat bowl is metal not glass. My oldest metal one was off when the last one was ordered and a bit of rust but not bad.

I understand not what a purest wants for restoration, but it gets the job done. I have had a glass one break a piece out from tractor vibration, I guess. Was not working were a tree limb could wacked it. Bowl was not lost just a small piece gone.

Old school mechanics would sometimes substitute an ointment bottle for a fuel bowl. The only new bowl assembly I ever purchased from the dealer say 8 years ago, came with a spun brass bowl. Talk about expensive, as that was the first tractor that I had been reviving, and blew my mind, as it was almost $200.00 in US dollars. That obviously didn't deter me from buying more tractors! It has paid to save old parts here, now if I could remember where I place them all, that would help. JM

at that price JM it would have been cheaper to machine one out of brass bar stock especially if you have a friendly machinist in your rolladex. i know the feeling "the bloody thing was here last week and now its grown legs".