Well, good news. She's back! The replacement engine that cost me 99p from ebay appears to be a winner. I've no idea what engine code it is, but its out of a Sirrocco (ca. 1990). I was told that it had only done about 70,000 or so and after hearing it, it cannot be far wrong. Much smoother than the other, not tappety, very quiet.
I've not tested how quick it is, although she pulls well. The power delivery seems different too. No idea whether thats because of the cam or something else.
Its been nice driving my misses Mini for the last week, but nowt beats the Veedub