Hi Mr. Sean N.
I thank You very much for your quick reply and the enquiries about the history of this differential.
I think, for us, it's becoming a sort of mystery.
Our supplier has never mentioned the real brand of the differential , he's just told us that it's running out and so , just to try to solve the problem we tried to get it directly in England.
Some dealer of salvage/scrap told us that it's a BMC Austin K9 , but we don't know anymore.
Now during the last sale , I got back the damaged differential and I replaced the crown wheel and the pinion so that I can have one differential as spare part.
Since you told us that it could belong to others Austin Truck models, I noticed that on the "new" crown wheel there are not the same codes that there were on the damaged one.
As attachment, You'll find what I have just written before.
I remain at Your disposal for any further information.
Best Regards
Marco
OLD DAMAGED CROWN WHEEL AND PINION.pdf