The Garrard Lab 80 is an idler-driven unit. The use of the Teflon-on-Teflon washers should work on any type of turntable where there is a separate platter thrust-bearing. Direct-drives might have the turntable drive spindle directly coupled to the motor -- not sure -- someone on this forum site will know about that.However, as long as the thickness of the original thrust-bearing is matched fairly closely by the thickness of the Teflon washers (might need more than two stacked or a thicker stock), this fix should work nicely.
Let me know how this works out if you are able to apply this remedy.