This might be a PITA too, especially if you use a printer, but maybe get larger ones and cut them down? Would work for hand written tags. You might have a hard time finding any other ID plates like you have already found. I think those are pretty nice and don't recall seeing anything similar before seeing yours. Maybe a glue stick would work to hold them on better? Very easy to use, but don't know how they work on plastic?
I actually thought Avery had just about everything in permanent and very few in removable, shows what I know about them as well, not much I guess? Sure seems like the removable were hard to find when I was wanting some a while back when we moved.
