I found one of these, model number 60-689199, at home, but had lost the manual. Some web searches didn’t turn up a copy of the manual, so, I decided to try and rectify that problem. Another unit was found at the 99 Cents Only Store, and I bought it (for $1.99).
I suspect there are thousands of these remotes out there. This page will help keep them functional. I made some errors and am missing a page in the device list, and I’ll fix that asap, so please follow this blog to be alerted to changes.