Formations did a Ram OP kit in resin but I think Rob is not producing anything at this time. That is a shame. Verlinden did a gun tank years ago which recieved mixed reviews. Not sure when was the last time they produced it. Those are the only Rams I am aware of.
Out of curiosity, I searched ebay a few months ago for any Ram tanks and got nada. I spent years building nothing but tanks but for a few years it's been sci-fi and cars.
The Verlinden one sucks and is out of production. Formations closed up a few months ago but sold the line to a shop in Canada who is offering at least some of the range again. I do not know if the Ram is available.
The problem with the Ram is that I can't see a mainstream kit of it... it is too esoteric like the Australian Sentinal.
S-model out of Poland has a Ram ll EO33 a Sexton ll with the very rare Canadian dry pin track system EO39 and the Canadian "Ram-Kangaroo" Mk. I EO44 only thing is their resen and pricey Can $ 61.72 + shipping or USD 59.78 + shipping, if I had the bucks I'd get the Kangaroo for sure. Hope this helps .
The CDP tracks are coming out in plastic soon. I believe from Panda. I had two S Model kits before, the 8.8cm Waffentraeger and the Staghound. The Stag looked pretty good and was a mix of resin and vacuuform. THe Waffentraeger was a pirate copy of the ADV kit.
The S Model Ram seems poor. For on it includes rubber molded copies of the inaccurate Tamiya M3 Lee roadwheels which have the wrong number of spokes. It seems also to be based or copied from the Verlinden kit and H and K conversion.