There probably is, although it's easy to write their name on the loo-roll before you wipe. I recommend using a sharpie rather than a biro. It's very cathartic. The DIY method also means you can smear the name of just one person at a time or several, whereas you'd be a bit restricted with pre-printed stuff.
Maybe selling the loo-roll packaged with the sharpie is the way forward? Or, even better and tapping into the 'mindfulness colouring-in' thing, you could print a blank outline of a face on each sheet to be coloured-in (with the supplied pack of felt-tips) to represent the hexing subject.