10-15 years ago, you could spend a few hundred bucks to get CNC machined bicycle mags, which were designed to be screwed to a hub's spoke holes and to the holes in a normal aluminum rim. Those wheels were intended for choppers and
"kustoms", so they had a lot of different flashy patterns. Because they were machined from a single plate (like a giant chainring), they had some drawbacks compared to wire-spoked wheels: They were heavier, weaker, more flexible, a lot more expensive, and essentially non-repairable when they went out of true. I notice that it's difficult to find even a picture of those wheels now, so I guess they didn't hold up very well.
I found a picture of some other
older metal mags with a stronger design, but this kind of wheel would require a special rim. These would also be non-serviceable in the usual sense.
I'm curious what you mean to accomplish by using mags? Is it a matter of aesthetics or mechanical reliability? Because if it's mechanical reliability you want, you can do better, cheaper, by upgrading your wire spoke wheels with a stronger rim, high-quality butted spokes, and expert assembly.