Someone help me with year model on Mariner 6hp and 8hp please have serials numbers

[bale1984]

What year model are my 6hp and 8hp mariner?? Help please I have 2 mariner engines both made in Belgium want to no what year they are so I can buy parts thanks. 6hp serial number 9543971 B4822 / VERVIERS 8hp serial number 9793196 B4800 / VERVIERS