Where can I find 80mm rubber wheels?

Lynxmotion Rovers, Sumo, and Tracked
1

I’m doing a school project and I am having trouble finding a decent 80mm rubber wheel that’s not insanely cheap.
Can any of you help with finding a wheel?
Thank you
(My budget is max $50)

2

80mm = 8 cm = 3.15". Would around 3" to 4" be ok? What weight will each wheel need to support?

We offer quite a few in that range here:
robotshop.com/en/robot-wheel.html

Some ideas:
robotshop.com/en/actobotics- … RB-Sct-417
robotshop.com/en/actobotics- … RB-Sct-655