A wireless keyboard that uses a receiver that plugs into a USB port might provide limited functionality.
I picked up one of these
from somewhere a couple of years ago on sale for less than the price at the link, thinking to use it on a PC connected to a TV.
Out of curiousity I plugged its receiver into an S3 HD and some of the keys did something, but I don't remember which ones or what, and I don't remember if I had to reboot the TiVo first to get it to notice the USB receiver or not.
I tried it just now on a TCD140060 that I could get to the back of, and no response.
So I'm not recommending the purchase of anything, just an avenue for exploration.
If you have a wired keyboard with a USB plug instead of P/S2, you could try that as well.