In the parts list (p153) for the reader in 21299e.pdf http://ww1.microchip.com/downloads/en/devicedoc/21299e.pdf Described as a custom part Googling for 13.560MHz brings up a few who may be able to supply -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist