There is no Honda Dream MF in Honda Museum. They have only Dream SA, which was very common bike.
There were 4 main Dream models in these times. SA (12 HP), ME (12 HP), SB(14HP), MF (20 HP).
MF was the rarest, the most expensive and had the most powerfull engine and some gadgets like you can see.
My MF has got old Japanesse papers from registration and Honda certificate that it is matching number and when was produced.
Please see how it looked when I purchased it 6 years ago.