I am trying to order the parts for an ASM-1 synthesizer and am unsure of a part. I was ordering from Mouser. The parts list says I need 2 2N4856, PN4391, or NTE-466 N-channel JFET. Doing a search on any of these numbers doesn't turn up any results. Could somebody eather help me or recommend an altornate part? Thank you. Josh Randall