As you say, Vietnam far more likely.
I received these comments from Andrew Galt.
Thanks for the link, definitely not pre-war looking at the dash/speedo. Pre-war speedos were black and the bars on the dash were only fitted on the later small boot models for about 12 months, but there should be four of them. Having said that it looks to have narrow rear wings which were only fitted to early pre-war cars. The real giveaway is the shape of the rear edge of the doors, which on this car (as far as I can tell) is vertical and square at the lower rear corner, whereas on genuine roadsters the doors angled towards the rear as they dropped down. The spare wheel cover is odd.
The majority of the imitation roadsters were fabricated in Thailand and Vietnam where French cars (saloons) were available to convert.
Roger