I can't stand 'Down The Line' but there are old episodes appear on the British Comedy Channel, together with lots of Hancock, Horne, Williams, etc. I usually listen to several hours per day of the BCC's output, typically when I'm posting here.
Schedule here:
http://rokradio.com/british-comedy-channel-program-guide/
(NB: Note that the schedules are in GMT. Remember to add an hour for BST).
Link to listen to the programmes here:
http://rokradio.com/
(There are also some classic British comedy programmes on the Old Time Gold Channel there).