https://www.ebay.co.uk/itm/Wesco-Folding-Oil-Can-BSA-WM20-Matchless-Royal-Enfield-WW2/223759041155?hash=item3419140283:g:UtUAAOSwce1d1VGx

I'm sure I saw one of these forsale on Ebay about 2-3 weeks ago for £200 ? the seller used a photo of his BSA M20 to advertise it.