Can somebody please help me find a decent corldess phone in UK that
will support 2 phone lines (like the ones widely available in the
USA)?

It should also have the usual fearures that are currently available on
the UK cordless phones. The main ones are multiple handset, handsfee,
caller id.

It should be no more than £100 for a twin pack.

Very difficult. The choice is between the (old) BT Airway system or
using two channels (one line) on a BT Diverse ISDN system. Unless you
are exceptionally lucky in finding a second-hand system, neither will
be within your price range.

What most readers on news:uk.telecom usually recommend in this
instance is using a small 2-line PBX and connecting the cordless base
stations to the extensions (one station per extn). Call transfer,
intercom etc is then handled by the PBX rather than the facilities
within DECT/GAP.

Owain

You could also check "that well-known online auction site".co.uk as
there are some appearing for sale quite frequently at the moment.

Owain