/diy/ - Do It Yourself

I need to find tracks for a robot I'm making, but I'm having a hard time trying to find ones designed for that purpose.
I'm looking for tracks ~1.5-2mm thick, ~1cm wide (I can cut them if they're wider), and 40cm in perimeter (20 cm long).
I've been trying to find something in aliexpress and e-bay, but something lik exercise bands are probably my best option.
Does anybody knows a source of a variety of rubber bands (e.g: industrial rubber bands used for seals or whatever)?
I don't care about the source, as long as they have a good grip on the ground.