My suggestion is to contact the manufacturers, see thomasregister.com ..
GWE

McMaster is where I started my little search. They have the following
thread pitches in the form of taps for sale in 3/4 diameter:

40
32
28
27
24
20
18
16
13
12
10

To me, that means that someone, somewhere is selling 3/4" bolts, threaded
rod, or studs with those thread pitch combinations... But it's not always
the case, right?

I've found a few, but not all. And then the question is... Why do they
have a tap available if the bolt that goes into the hole doesn't exist?

I might have to go to TR and see who they list... But I'm looking for a
quick, one stop shop for these of course... At McMaster's pricing.

Regards,
Joe Agro, Jr.
http://www.autodrill.com
http://www.multi-spindle-heads.com

V8013