Thanks The late Stu - I've adjusted your entry, and after a comb through the discussion forums, added a few more listings (auction house, abebooks, amazon marketplace) that we discussed. Some outliers (as always).

Here is the discussion for that very first auction listing in 2012 (it was eyebrow raising at that time!)

You can add my copy to your list if you want: £211.68 on Abebooks, listed and purchased on 8 July 2023.

Paid mine £294 in october 2019 (fine, clipped, eBay)

additional data for my copy (fine, clipped, abebooks)

I know you say variant Mr Underhill, but they’re all the same no? It’s just that the clipped ones were sold outside of the UK only originally, so the £7.95 was removed.
Does that make it a variant?