I have a pair of power steering cylinders that require a 1 1/8" ball
mount on the valve end. I've only found one...on a travel trailer sway
bar. Every camper supply I've checked has 1 1/4". I didn't note the
brand of the one I found.

Any suggestions on source?

Ditto.. I am currently looking for a pair of 1.0 inch ball studs for a
trailer hitch for a 1957 aluminum one-wheeled trailer.
I spent about 4 hours searching and also checked some towing supply catalogs
with no result.
All I could find was either up to 1/2 inch, or in metric sizes up to 19 MM.
--
Stupendous Man,
Defender of Freedom, Advocate of Liberty