It would be nice to think that someone in the NHS (or one of its Agengies) would maintain such a database, Matt; but somehow I doubt that it exists (although I should be more than happy to be proved wrong).

But here's a couple of thoughts:-
Why not look at EoL in another way ... assume (or simply declare) that everything is no longer supported (by the OEM or Supplier) beyond a certain age unless documentation exists to show that is
is still supported. Fifteen years, say (although I know some might suggest ten).
And also why not broaden your criteria to include equipment that is proving (or has been) troublesome, using indicators such as:-
1) Frequent breakdowns
2) Difficulty in getting spares
3) Excessive amounts spent on maintenance over the years
4) Long periods out of service (awaiting repair,
etc.)
5)
etc. ...
Also, dare I add:-
1) No longer being used (or "liked") by the clinical staff!
2) Superseded by new clinical techniques ...
etc., etc.