markings on the back of Buffered Grappler+ card:

ORANGE MICRO INC., 1983
ASSY NO, 72 BGP 00001 REV A

PART NO. 95PCB00003


yes, that is interesting,

https://archive.org/details/TheBufferboardManualAppleIIGrapplerEpsonAppleParallel/page/n3/mode/2up

the bufferboard manual schematic shows the mention of 6M and 7M clocks:

[Linked Image from i.imgur.com]