Wheel adapters are not illegal. I don't personally know if spacers are illegal or not but don't use them, get an adapter.
Adapters have their own lugs and a set of lug nuts for the stock lugs.
Spacers are just that...blank holes that fit over the lugs, and require longer lugs.
Either way, unless you're doing something downright stupid...like pushing the wheels way, way out...the offset load on the wheel bearings is minimal as long as your new inner sidewall is in about the same place as the stock inner sidewall.
Most of the fabrication shops should be able to make you one, but it might require going there with the vehicle for measurements and test fit.
I've been running adapters in the front of my 1st-gen for several years now, on and offroad. The inner and outer lug nuts need to be checked extremely often at first, then less often...now I check the outer lug nuts regularly as part of routine maintenance but only check the inners during front end maintenance or after hard trail runs.
I have heard of many failures, all due to shearing lugs on the hub or the adapter. This is NOT an install and forget modification, you MUST check the outer lug nuts REGULARLY since it will take time for the lugs to seat, and the inners must be checked as well in case your stock lugs are not fully seated.
In addition to failures, there are many rock crawlers, desert trucks and daily drivers which have been safely running adapters for years. What you get from them is entirely dependent on how you look after them.
-Sean