I have one of these since I was a kid, and its origin has puzzled me for a long time, but I don't think it's a Jonckheere. On closer inspection, it appears the Majorette modelmakers have been inspired by the Irizar coaches from Spain, especially the Korosti and Urko models. It's basically an Urko with the front end of a Korosti... but all squeezed into a midi coach format.

Korosti : https://www.flickr.com/photos/irizar_coaches_and_buses/12237452213

Urko : http://www.fotobus.es/data/media/20/Irizar_Urko_002.JPG