They have been kind of hard to find lately, I had an extra but sold it to a guy in the land down under a few months ago. He was on the hunt for one for quite awhile.

Might try these guys , spendy but complete:
https://www.parts123.com/parts123/yb.dll?parta~dyndetail~Z5Z5Z50000014a~Z5Z5Z58622~P349.50~~~~S4IG0OOGLT10889311880d~Z5Z5Z5~Z5Z5Z50000014x


1953 Chevrolet 3100
261 cu inch, sm420, 3.55 rear, torque tube still,omaha orange, still 6 volt, RPO green glass, side carrier spare, all done
In the DITY Gallery
Video of the 261 running

1964 GMC 1000
305 Big Block V6, sm420, the next cab off restoration