On 2012-07-03 21:16:27 +0000, newshound said:

Looks a bit like an iron waste pipe to me; don't recognise the collar
at all. What happens outside? One option might be to fit a new plastic
pipe through the wall to an existing iron stack outside (which is what
I have). Then you can have nice modern unbodged pipework inside the
house.

Thanks for the reply. I've just posted links to another couple of
pictures of the outside -- see my reply to Adam.

Your idea sounds promising, if I can get the old joint apart on the
other side of the wall without damaging it. How did you fit the new
plastic pipe into the old joint?

--
James