Despite phoning Tanc & them saying they'd check, I've heard nothing since. I also emailed them & sent a message on their website, but zero response.
An employee of Deltaworks emailed to say they couldn't find one.
Finally had a slightly odd email from Zagato saying 'check integrale.org.uk' - which as you pointed out earlier, says to email them for price & availability. If you put one in the basket, it says out of stock anyway.
Pretty useless all round then.
Seems maybe I take a punt on the German 16v one on eBay (they have an ABS sensor housing in the casting which I don't think matters) & hope it's ok - £275 down the drain if it isn't.
Could be I get this one sleeved, or bodge it with Belzona. Not too sure the best way to go.