"Rollo" wrote in message
...
Take it off, it looks as if it's held on by posidrive screws and attempt
to find any manufacturer's information on concealed surfaces and then try
and contact the original manufacturers of the handle.

If no joy with that approach then hawk the handle around your local double
glazing suppliers, one of them may be able to tell you the manufacturer of
the handle, or who used to/ still does supply them.

Good idea. Thanks.
--
WSB