Cheapest way to get easy toe adjustability in the rear?
 

I've been fiddling with DIY alignment on my BRZ and am pretty happy with it so far. The biggest pain is adjusting rear toe - the OEM eccentric washer is horrible to adjust. It changes toe by a lot with the tiniest turn, and it's almost impossible to tighten the nut without affecting the toe.

What's the cheapest way of getting easy adjustments? I'm looking for a threaded toe arm like in the front, ideally with a fixed washer to lock the OEM adjustable slot. Is the RockAuto MOOG arm at $70 a piece the cheapest way?

Yep, RockAuto Moogs (same thing as SPC) with some lockout plates. GKTech had the cheapest lockout plates I could find without resorting to cutting metal myself when I was last looking.

Only annoying part about the Moog/SPC is that you pretty much need to cut down a 22mm wrench to easily adjust them.

Why is that? Is the jam nut too thin for a regular 22mm wrench to fit?

Nah, as in a full size 22mm wrench is too long to adjust without being frustratingly slow. I cut mine down to be like fist length so I can more or less do a half turn at once instead of like a sixteenth of a turn before having to reposition the wrench due to hitting other links/ground/etc.

MOOG/SPC LCA
SPC toe arms for additional range of adjustment.