I have just fitted a new centre and rear box to the TZI which is the kind for the 16v having the oval polished finisher and very smart it is too.
So I have left over a rear box with the usual tailpipe which was new when I got it 6 months ago and has done about 500 miles since then.
The condition is spot on and looks "right" with the tailpipe being the correct length and angle not like the horrible cheap ones!, I purchased it from Wolsey House motors who told me it was "OE" but I have no idea if this is correct or not as there is no stickers.
It will fit any BX hatch with either a 1.905 fuel injected 8/16v petrol OR 1769 turbo diesel.
I can bring to the national if required.
I have a spare middle box which is useable which I will throw in FOC to who ever buys it.
It has the remenants of a sticker on it which is in french, and made in france on the box, plus a N part number so you ever know it could be a genuine one.