Secondary frame battery

[edgertdj]

I purchased a Dost Drop bike in August, 2023. Received the bike but didn’t get the secondary battery or the rear view mirror. I understand that the company is in receivership and my chances of getting my battery and mirror are near zero. My question: what after market battery will work on the Dost? I know it will fit on the frame but what make and model with the proper plug in will work? Any ideas who would sell these? There has to be something out there that would work without any hassles. Thanks!