[British-cars] Clutch cross-reference needed

[Mark Mason]

I'm trying to match a clutch friction plate for a Morgan trike.  It's
so close to being common that I'm hoping that someone has some
cross-reference charts that will point me to something I can get
locally on short notice.

It's Beck & Borg (AP), 7" diameter (which is unusual), 1" 10 spline
shaft (which is really common), 4 spring (although I don't care about
the number of springs).  There are some 7 1/4" and 7 1/2" plates
available, and I'm pretty sure I can turn them down, but a lot of the
listings I run across tell me they're 10 spline but don't specify
diameter, etc.

The closest I've found is an AP CP2012-164FM3, for
Alfa/Talbot/Triumph, which is 7 1/4", but it's sintered, which I don't
want, and AP doesn't list it anymore, so I can't cross-reference it to
something I might be able to get.

Sunbeam/Riley/Spitfire/Midget/MGA/MGTD all look close, but I can't
find enough info on them to know if they're close enough.

Any chance someone has a book that lists cluthes by dimension which
will tell me what other applications might be appropriate?