I encountered and my acquire a pile of DEC boards from KT or K&T (one paper tag mentioned this).
It's a vendor that currently doesn't ring a bell (will update this when figured out).
There a large pile of probably custom system boards, and a board with 32k x 17 bits + 64k x 17 bits (4116 and 4164 chips resp.) in the pile.
Also several boards with 6820 and 6800 processors on Flip Chip boards.
All are hex high boards. Some have 4 populated connectors with two flip chip spots blank, some have 5 (skipping one of the possible power slots).
Photos below, taken quickly today.
|has a cpu on it, also 6800|
|IIRC these are 6820s|
|the parallel i/o 6820s|