Probably just the P# needs adjusted. The notes are different sizes and colors...or the image could be wrong on one note. I will look next time I'm at my computer.
Library Media Specialist, columnist, collector, and gardener...
There's only one 500 pengő type: http://banknote.ws/COLLECTION/countries/EUR/HUN/HUN0117.htm
I'm afraid it's just that the images are showing different colours. My example looks more like the second one and the dimensions match, so I'd recomend keeping that one.
Former Numista referee for banknotes from Ireland, Northern Ireland, Scotland, Wales and Saint Helena.