Jasper Broeks created some nice emulations of Roland´s Juno 106, Alpha Juno 2 and Jupiter 8 synths for Reaktor. These are in Beta and downloadable from the User Library (You´ll need to be registered). Here some of the original sounds:
You might want to check out these Reaktor instruments with one of our MIDI packs. In particular, probably best with one of our Synthwave packs.