Here’s the response I received from Aeon Labs regarding replacement for failed batteries. Mine are indeed the v1 with the numbered buttons, no idea they were that old, even when sold as new.
I opened up the remote and with a little soldering I think the battery can be replaced. Ordered a 5 pack of 302323 batteries from eBay for $12, hard to go wrong for that price. Will attempt to replace and see how that works.