So far I've only been able to find such parts for 3.5mm minijacks,
not the
2.5mm that Sennheiser thought fit to use on some models.

I found FE67X from Maplins after my last post, which could be useful.

In that case what about item COM638 on
http://www.lektropacks.co.uk/dept.as...tom&dept_id=52

But that above also looks quite useful. I'll have to decide whether to buy a
new plug to stick on the end of my Sennheiser cable (which I might find
awkward, and the barrel might not fit through the opening in the earcup), or
to buy a whole cable as above but which might be noticeably different in
quality, or just try both, which still works out a lot cheaper than buying
the Sennheiser part.

Thanks, for the lektropacks and garex urls, hadn't heard of either of them
before, usually I can get this sort of stuff from www.studiospares.com.

Cheers,
S.