They lived a very short production life. If memory serves correct less then 5000 were built over a two year period and a lot of the MR stamped guns had barrel drop and were typically sent back to Remington who paid the owners out without replacing the rifle.
It took me about two years to find mine and I considered it essentially a unicorn. It’s JM stamped and the only one I’ve ever seen for sale. Marlin keeps making noise about resurrecting both it and the .308 marlin but who knows if they’ll ever bring them back.
The good news is that components for both are relitively easy to find online and when I find guys with components for either rifle on the second hand market they’re usually selling them very cheap as there isn’t much demand for them. I laid up a lifetime of supplies for both cartridges early because it’s hard to say if they’ll be around in another 20 years.
The JM stamped guns are typically very accurate (as per internet lore). Mine will do under an inch at 100 and about 3.0-3.5” at 300 with three shot groups. Besides the factory 200 ftx and 250 corelokt I’ve also had good results from the 160ttsx with the polymer tip rounded off. Currently I’m seeing 2800 FPS from my load and haven’t found what I believe is a max powder charge. Over on marlinowners there’s some info on shooting 180 accubonds with the tip filed down but I haven’t taken a trip down that rabbit hole.
Good luck finding one, they’re the only purist, long range “modern” lever action IMO.