There are cow tags for sale in NM. Going rate is $500 -$650.
These tags are issued to private land owners by the NM Game and fish to compensate for wildlife depredation on private ranch land. Most tags will be unit wide rather than restricted to an individual ranch. To get an idea of the size of game management units you can look at unit 52 for example on the NM G&F web site. Unit 52, bordering Colorado, includes a vast portion of the Carson National Forest including the Cruces Basin Wilderness Area -no fences!
I’m happy to help with more info if you are interested.
good luck
adios
David