This is a listing for Alembic electronics (http://www.ebay.com/itm/Original-Alembic-guitar-electronics-filter-pots-pickup-selector-complete-working-/111588513839?pt=Guitar&hash=item19fb31982f) without the pickups. I've never heard of an Alembic push-button 3 pickup selector. Did they ever produce such a beast?
Bill, tgo
Interesting indeed, looks like it could have been done by Alembic (though you would also expect a connector for the output on the switching board)
Coincidentally, the same seller has 3 Alembic pickups listed separately. Interesting find.
3 pickups?! Coincidence?!?...... Pshhh... Thats just swamp gas!