Gearbox (5-speed, manual) needed for 1987 B2 1.8 CL, petrol

[Gog32]

Hello,
does anyone have a gearbox, as above, for sale?

My B2, with the 1.8, "DS" engine has just reached 169,000 and the gearbox or differential is making a growling noise when on the move - probably due to a worn bearing or diff. pinion.
I am able to remove the box but don't think it is worth dismantling, as gaskets, bearings, etc. could be difficult to obtain and setting up is a bit involved.
I live near Cardiff, South Wales and could collect, depending on location.
Any help would be appreciated.

Thanks.