I don't think anyone right now including Marlin are offering a new production rifle in the .444 Marlin cartridge.
I don't know this for fact but I would assume at least with Henry the popularity of the cartridge is the deciding factor. Not weather it is a Marlin, Remington, Winchester or who ever designed cartridge.
I would love to see the .444 offered in a few different rifles by both Marlin and Henry.
Perhaps with some states that once where shotgun only adopting straight wall cartridges for hunting there may be a small resurrection of the .444. I would buy one!