I was able to find the slide rams on the Trekwood site for your rig, and was surprised that the rams have aluminum bodies instead of steel, so maybe that is why they are not made to rebuild. They use dimensions of fitting to fitting, and show 38", 32", and 24" rams.
https://www.trekwood.com/products/58...luminum-342328
https://www.trekwood.com/products/58...luminum-354180
https://www.trekwood.com/products/58...luminum-339031
It is very strange that the longest ram, 38", is the cheapest at $212.46.
The 32" is $300.39, and the 24" is $240.30.
I'm also pretty sure that the slide rams on our 2012 Montana have steel bodies and appear to be rebuildable. Instead of trying to get them rebuilt, maybe a hydraulic shop could make new rams from scratch out of steel, and you may never have to mess with them again.