I think Mike Nixon's Vintage V-12s at Tehachapi bought a lot of Merlin blocks and spares over the years, hydroplane Racers was one source as I recall.
I had a chat with Pete Rushen at Duxford once, he was dismantling a Merlin to get it running again; I think he said it was out of a Mossie and was heading to Australia - probably a swap for Beaufighter parts. TFC had probably already sold on their Mossie TV959 which is one of the ones now flying again.