Another idea:
Look for rubber or soft plastic (vinyl or other) tubing with inner and outer diameter to match the hub/tire size, respectively, then "slice" individual tires off the end. Cooling or freezing the tubing might facilitate even cuts with a SHARP blade (when I want the cleanest cut possible, I use either a scalpel blade, or a DOUBLE edged razor blade... a trick from my days prepping samples for electron microscopy).
Good luck!