WW2 West Riding CD First Class Ambulance Driver Badge

This badge (currently up for sale on eBay) was new to me but other collectors have intimated that similar badges have been seen before. Alas, it was also reported that similar badges were copied and reproduced several years ago. Going by the type of embroidery and the backing on the badge this could be original but without provenance it's impossible to say categorically if this example is the real McCoy.

WW2 West Riding CD First Class Ambulance Driver Badge