2-way telephone splitter (Southdown AL5)

Anyone got one of these spare, allowing you to plug 2 phones (*not* a phone and a modem) into one phone socket?

I need one to help out an elderly lady so she can have a cordless phone upstairs.

Of course I could get one online for £2.50, or at any of the big DIY stores if I didn't mind spending perhaps the same again on petrol, but I can't believe I haven't got one in a box somewhere.

For the above reasons, please don't bother to reply if you live more than a mile (or two) from Southdown.