John H
You'd have done well there, quite a lot of Duggie powered generators. Not the same as the bike engines, I
think they were 250cc SV. Not sure tho. Piles of dead BSA M20? 500cc SV, all rusting away in the rain. Matchless/R Enfield, probably others I don't remember. Hundreds of new engines, incl. mags and carbs. Whole damn lot sprayed with green paint, HT leads, plugs, the lot

£3 each, IIRC. Do remember recon. Merlins, crated were £80. wonder what they fetch now?
I don't suppose the plumbing is still on your island, what with the price of scrap .. or what was etc. Lucky to be able to swan around the Pacific in a boat. I once had two weeks on the Norfolk Broads, not exactly 'Blue Water' cruising. Rained most of the time, so we frequented pubs most of the time. All was not lost ...

Graham, John BS, looking at it as you say, yes, an item is worth what someone is prepared to pay. Nicely made marine engines, I don't suppose they are still produced? As far as I know, all the makers of up-market engines went pop. Morton 5, Taplin, Channel Island, more probably, I forget. I seem to remember a 4-stroke single (KB?) about 20 yrs. ago.
Skiprat, can you confirm it had an external PSU. I am pretty sure it did? But it was 40 yrs. ago. ... Yeah ...
'not part for a weapon' ... you can tell North American history is a bit sparse

.... If it went back a bit further, the word 'Trebuchet' may have occurred to the vendor ...

Dave BC