Thanks for everyone who replied here.

My London Fog maincoat arrived today - stone MINT as it came from Florida where the owner only wore it when travelling. Perfect size too, the 40R

It also cost all of £5.20 plus shipping. Out of all the coats on Ebay (and there are always loads) it had THE worst photo but great description.

Seller was old school super friendly as well, even took it off ebay to relist as a buy it now for me when Ebay wouldnt let her change to Int'l shipping.

When I think that years ago I used to buy things in a 44 to get what I thought then was a baggy 50s vintage look in contrast to the 80s skinny. Now I buy things that fit properly in contrast the 00s baggy oversized nonsense.

Will post an image of the coat later in the week.

Thanks Staceyboy, Russell, 1966 and Chris H

With all your help and input I avoided a disaster on sizing with my London Fog adventure, my £5.00 70s mint example can now be seen in full glory over on the ivy Style For Today thread....