Call/email around. I'm sure someone has some. Here's a start:
This guy (Frank Norman) has one of the fully serrated cheap ($29.00):
Also try emailing Ruff's Saddle Shop (they don't have a website): firstname.lastname@example.org
They will, at the least, have some limited edition old style ones with the "Professional Rodeo Cowboy Association" logo on them.
I've done business with both and have not had any problems. Good prices, good service.