Mystery 1970 core board

Hopefully collective wisdom can help on this one - does anyone have a clue what system this core board was from: http://www.classiccmp.org/acornia/tmp/coresmall.jpg The curved edge connectors (presumably to make board insertion easier) are quite distinctive, plus the way the power's fed in via an edge connector on the "far" side of the board. What's interesting to me is the core ring size; the TTL ICs on the board have 1970 date codes, but I didn't think that the rings got quite that small until right at the end of core's era, more toward the end of the decade. It seems to be 8 blocks of 64x64, i.e. 4KB. p/n on the main board of 2001000755, and just hidden from view under the core daughterboard is a logo that says "LEC", which I suppose might be meaningful. There's a bigger (2181x1863) image as "coreboard.jpg" in the same dir if more detail helps (I doubt it), but it's 2.4MB so maybe save Jay's bandwidth by only looking at that one if you absolutely have to :-) thanks, Jules