Team prime is the best thing out by far.. I think you can get them at apexrc pro shop

Greetings: On my R125.2, I run a Yokomo R12 Thrust Bearing (Part# R12-24TB). Per the Yokomo instructions, I just add the Thrust Bearing between the outer hub bearing & the diff thrust cone. The axle threads are plenty long enough to allow this install without any modifications. I'm no pro, but this works well for me.
P.S. You could also try a Slapmaster thrust bearing kit, but they cost more $$.