I can find only one source from the internet where that car is mentioned and it's named Aero Minor III Spezial. But I have seen the picture on some site I cannot find anymore, because I have saved it to my computer as Aero Minor II -based Jawa "M". Although Minor III never made it to production, I would choose the first version because Minors produced after WWII were Aeros, not Jawas.
So I will choose Aero and III.