CZ 250 Motocross Engine 1968 Works 250 ccm. J. Robert

CZ 250 Motocross Engine 1968 Works 250 ccm. J. Robert.  This engine came from an auction in Florida, it is in rough shape, when I started taking it apart I found engraved on the gear what you see in the photos "1968 WORKS 250 CCM. J. ROBERT", I don't if that means anything, but it is intriguing, the serial number of the engine is 980-02-00199, as I stated the engine is in rough shape, it has had water in it, the crank and transmission are frozen, rusted, the cases have corrosion, the one case has some broken pieces, the side cover is cracked, dented, all the metal parts have some rust on them,  the cylinder looks to be in decent shape,  the cylinder has alot of rust on the bore but no broken fins, see photos for condition.   I realize the price I'm asking is probably too much for an engine  in this shape, but with the possibility of its historical significance I wouldn't take less.  I can send more photos if needed.