My question is in two parts.

Firstly I would like to find a list of sailing boats with overall
lengths between about 23 feet and 40 feet (about 7 m to 12 m) which
have been in production in the UK, US or Europe since the mid sixties,
or which are still in production.

I would expect the list to include (but not be limited to) the
following boats :-

Arpege,
Bavaria 32,
Bavaria 37
Cutlass 27,
Elizabethan 29
Folkboat,
Hallberg-Rassy 352,
MG 30
Moody 31,
Nicholson 35,
Oceanis 351,
Oyster 39,
Rival 34
Rival 36,
Rustler 36,
Sadler 34,
Seahawk 35,
Tradewind 35,
Trintella 29
Twister 28,
Vanouver 36,
Westerly 37.

Secondly for this list of sailing boats, I require information on
their range of positive stability - the angle of heel at which the
boat stops resisting capsize, otherwise known as the Limit of Positive
Stability (LPS).

I understand that an International Measurement System (IMS)
measurement certificate shows this stability range for individually
measured yachts, and a yacht designer can calculate it. ("Calculated
Limit of Positive Stability"). The IMS appears to be managed by the
Offshore Racing Council (ORC).

I will not be wholly satisfied with the IMS Stability Index, unless
the data is sufficient to readily calculate back to the LPS.

I will not be wholly satisfied by the capsize screening formula (which
has been described by John Rousmaniere as a quick-and-dirty way to
estimate whether a boat might turtle and stay turtled) developed
during the Capsize Project undertaken in the early 1980s in response
to the 1979 Fastnet Race calamity. The project was co-sponsored by the
Society of Naval Architects and Marine Engineers and the United States
Yacht Racing Union (now US Sailing).

the only kind of stability information you are goign to get is a
textbook answer from calculations. no body can cover all the
possibilities and factors that will occur when a boat is at sea and
which could affect the stability of the hull. at the moment the
stability index and all the other stuff you mentioned are your best
bet.

there is a database of yachts on the rya website thta has over one
hundred different types of yacht. there is also all the stability
information adn dimensions and everything with each one of them.