I can't help you locate anything but it might help to know that some other manufacturer's foot switches work with the Beseler. I'm am using my old Kearsarge FS with my audible.
I've been looking for one of those myself. There was one on the bay less than a month ago. Went for $15.00 I was going to bid on it but I was making a reducing back for the V-8 and forgot to bid. ( I can hear some out there now"serves you right you damn dirty sniper") Please lets not turn it into one of those threads. Neal, thanks for the info about one that will work.
Any alternative foot switches would be fine; I'm not wed to a perfect match, just a functional one.
I have an eBay alert in the Darkroom section for "foot", and haven't seen much. There was one last month, but I thought the connector looked pretty different.
I recently acquired a Bessler audible timer with a foot switch. The foot switch is from Micro Switch in Freeport, Illinois. Did a quick serch on Google, and they may have been acquired by Honeywell.