Brake rotor / hub not aligned

[Tattooo]

Space is too tight to permit any offset.

Yep that's exactly what I said..............

You need to buy the correct rotor for that aftermarket wheel..........

[47str8leg]

As others have mentioned , there is no way to fit. It is not off left or right but up and down Those wheels were made in Japan I believe so, perhaps a rotor from a Japanese bike from the era the wheels were made might work . Unless of course, like Harley, they made a proprietary disc for that bike. Meaning , they deliberately made it an oddball so you could only by the disc from them.
Just a random thought.

[47str8leg]

Give us the center point between the holes in the hub. I saw one online in a video of a John Harmon bike. Doesn't have a great shot of the front wheel but it looks like it has a mini disc like an Airhart brake. I have one of those disc brake set ups on a bike I'm doing now. I could let you know.