Thanks for all the suggestions guys.
I've checked the coverage of the ApoNikkors from Dan's links, looks like they only cover 42 degrees so I want 760/11 or up (you're right, the data I had was looking at 1:1, so was wikipedia's data, methinks me should edit it to clarify).
(coincidentally, there's an apo-nikkor 760/11 listed on the bay right now, wish me luck).
And yeah, it's going to be infinity only, so can't get away with smaller lenses.
Aero Ektars are one that I've heard of before but didn't think about including in this search, I'll have a look for them too.