That engine has a most wonderful shape.
It does, and BSA enthusiasts went into quite a snit when BSA went to the A65 engine in 1962 with the smooth egg-shaped timing cover - didn't look "mechanical" enough for the true BSA type! But since the A65 used a crank-mounted alternator rather than a chain-drive dynamo, and points/coil ignition rather than a magneto, the "Y" shaped cover didn't make sense any more ....
If the engine truly is in good shape as advertised, probably needs a magneto rebuild to get the old capacitor replaced, then $1800 might not be a bad deal - get the engine and transmission out, flog off the chopper stuff to the chopper crowd, see if the frame's recoverable, and you might have some decent spares for your A10 collection ...
Lannis
