From my experience.
The front guard is still available from Kawasaki. Stick with the OEM one for the front. Whilst it is not an exact of the 83/84 unit (as it has been superseded along the way) but its pretty close. For “RACE” plastics go with the DC ones, they aren’t the best fit but they are cheap. For the “RESTO” or “SHOW & SHINE” go with Nightmare.
Too many people give DC an unfair kick in the guts. Yes they aren’t the best fit & finish but they work and in my experience with my 83 KX500 & 84 RM125 they are reasonably durable. If it wasn’t for them there would be a lot of bikes that wouldn’t be on the track in ½ reasonable condition. Also got to say that there customer service has been good from day one. Whilst I hear grumbles about the product, I have yet to hear a bad word about their service.
I use them and will continue to do so with the knowledge that they are going to provide a bit of extra work to fit and they may not look as good as some of the other suppliers but, ...... they are priced accordingly.