Went searching and all I could find for contact info is this email concor@con-cor.com and this phone number (520) 721-8939 If no response on either of these, no ideas.
If Don has a hobby shop nearby, he might ask the shop owner if he/she is aware of a direct line to Con-Cor for retailers.
The Concor website has a message dated July 3rd, 2020. I will summarize certain points mentioned. 3 month payment plan for purchases $250.00 and above. Parts and repairs are delayed due to unavailability of replacement parts. Will be dedicating time trying to catch-up on <shipping?> back-orders. Phone service is unavailable, contact by email for new orders only. Concor@concor.com. There was no mention of Covid19 or any issues associated with that. Sent from my SM-J737T using Tapatalk
FWIW... the ConCor PA/PB units I got in 1983 kept me in N scale when I got 'back' into model railroading 38 years ago. They cost me about 35 'Simoleans' each... back then ...which was not cheap. Sent from my SM-J737T using Tapatalk