There's no such thing as a "Ruger only" 357 load. Not from any manufacturer, period, end of discussion.
There are some handloading notes available for the two strongest 357 wheelguns ever made: the Ruger Redhawk in 357 and the FA '83 five-shot 357. Some hit 60,000psi. But no manufacturer has ever loaded such stuff, let alone labeled it "Ruger ONLY!!!"
The heaviest, hottest 357 ammo I know of is the Buffalo Bore full-house stuff followed by Doubletap's best. Buffalo Bore is very likely loading to the old SAAMI spec of 43k instead of 35k. You can shoot large amounts of 43k 357s up around 800ft/lbs energy in the mid-frames. No problem.
IF you re-chamber a Ruger 357 mid-frame to 45LC, you'll face the same pressure limits you'd hit in a NewVaq45 - due to thinner cylinder walls.