I found something very cheap for an dob alt bearing.
It is the nylon strap that they use to pack heavy boxes.
Very slippery when running on teflon.
And you can glue it with tarzans grip.
I just tried the movement after a couple of hours and it is still very smooth and not too slippery.
Looks like the perfect alt bearing material.
And the best thing is that you can get it for free.