"Dan Lanciani" ddl@danlan.*com wrote in message
...

snip
Unfortunately, the pin appears to be a non-standard size between 5/8" and
3/4" (maybe a little more than 11/16").

18mm

A machine shop was able to turn down
some 3/4" stainless rod, but it may be a bit too small and it isn't clear
what
stress it can take.

You need 4130 steel, probably, and a new tube of the same material. That
will make it easy to match sizes. Go bigger if necessary. Then, look for a
welder certified to weld 4130 to pipeline code or boiler code.
--
Crazy George
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