I have the following to trade for cacti cuttings or other cacti seeds that will be outdoor hardy in Zones 7/8:

Seeds:

Ferocactus wislizenii (Chihuahuan Desert Barrel cactus)

F. rectispina (Long-spined Barrel cactus)

Cuttings:

Teddy Bear or Jumping Cholla

Prickly Pear (native Chihuahuan desert species, Opuntia species, but not id'ed yet)

Cholla (native Chihuahuan desert species, Opuntia species, not id'ed yet)

Opuntia ficus-indica (only 2 or 3 pads)

Cattle Tongue or Ox Tongue (Opuntia)

Also looking to find other cactus/succulent gardeners in my area (southern NM)