"Lobster" wrote in message
...
snip
Trouble is, it was a bespoke one, made by someone quite a distance away,
so
I want to buy a replacement coupling and fit it myself, if that's what's
called for.

Obvious way to go is to remove the hitch (you will have to do this sometime,
anyway) and take it to your local dealer.

Look in the yellow pages for Indispension dealers who tend to have loads of
trailer bits, and caravan dealers and yacht chandlers who often carry spares
also.

They will be able to look at the hitch and match it to whatever they have -
much easier to do when they have the hitch in their hands to compare with
new stuff.

HTH
Dave R