I really enjoy discussing the Winchester .444 Marlin Rifles. I have no idea what their value might be.
If you are going to purchase a Winchester in .444 Marlin, check the twist rate. Some of the early rifles had a slow twist. My 17.5” Timber rifle has a 1 in 12” twist and I believe all of the 20” carbines have this twist also.
There are a few little things about the .444 Winchesters to bear in mind.
With wide meplat bullets they require deeper bullet seating. This is not a feeding issue but due to th inability of the cartridge to make the turn from the loading gate into the magazine. The Winchester does not have the cutout in the left side of the receiver as in the Marlin rifle.
For example the 310 grain Lee bullet requires a COL of 2.490” for smooth and easy loading. I am able to push the 310 grain bullet to 2,020 fps and a little faster using Hodgdon 4198.
I like my Weaver K2 on my Winchester and shoot deer in motion in the thick brush. I have a 5 minute Lee Dot on this scope and it is quick.