Went with wrong board house. JLC seems to run 6 layer promo for 2 years now. This board is $36 for 5, $100 gets you 50 pcbs.
It seemed like it might be coming to an end when PCBWay suddenly had no reasonable payment options, but JLC has been great so far (and I believe PCBWay has credit card payments sorted now?)
(Just wish I had far more free time to spend on hobbies, there's so many possibilities with 3D printing, microcontrollers, and custom PCBs now all so readily available)