Texas Staghorn Ferns sells a remarkably wide selection of Platycerium, as well as a number of other interesting and rare plants (Huperzia/Lycopodium/Tassel Ferns). I've purchased plants from small pups all the way up to fairly mature specimens. The plants have been healthy and well-cared for. I recommend ordering plants from this company; I've always felt well-treated! They may also open to trading rare plants, BTW.