On Fri, 19 Jul 2013 11:37:27 +0000, Adrian wrote:

So. Anybody know of any similar 4-wire switches?

Well, Screwfix certainly don't.

I am sorry that you have had to email Screwfix Direct regarding the
number of wires in our Switches.

The Screwfix Direct Product Support team has advised that we are only
able to supply the information as shown in our latest catalogues and
on our website at www.screwfix.comhttp://www.screwfix.com/ and
suggested that you should seek the advise of a qualified Electrician
in regards to the suitability of any replacement Switches.

Once again please accept my apologies that on this occasion we were
not able to assist.

FFS.