That engine with JAP above the magneto drive could be pre-1920, the lack of starting handle provision surely means the car is a Two-speeder and the windscreen looks like an Aero or Super Sports Aero type, pre 'V' screen.
Back in the fifties and sixties when the cars were still being used as every-day transport by many, all sorts of cannibalism and modifications were carried out just to keep the car running. Serviceable engines changed hands for a fiver and could be swapped in an afternoon.
It's probably a mix of several cars but does that matter?
Chris J