I concur with rbyrne, with the following caveats:
The "S" at the start of the partial VIN indicates St Louis assembly plant, and since the relatively low serial number means the engine block was likely allocated to a '65 vehicle, the "HD" (if it's really that) could possibly be a 327ci powerglide engine for a full-size passenger car... what I don't know is whether full-size vehicles were built in the St Louis assembly plant. The "102357" serial Vette would have been built in mid-November, which in turn means the engine sat quite a long time after it was assembled until the date it was used (although there was a strike in October and no vehicles were assembled that month). The same serial would have been built much sooner if it were a passenger car.
So, a lot depends on that last suffix on the block stamping: is it "RD" (Corvette) or "HD" (passenger car)?