FLIEGERII is spot on... to the best of my knowledge, HUKI never made any helicopter toys. But, who knows, maybe one will turn up sometime!?
Arne has shown quite of the few HK toys out there... I might add the following based on my research to date:
The HK-560 Strato Copter toys are by far the most expensive and desireable HK helicopter toys. The toy came in the two versions shown above with some variation to the rotors.
The HK-565 came in both clockwork and friction versions. The clockwork version used the same box as the friction versions. Typically you see the silver/red/yellow toy, but there is also a yellow/blue variation out there. And, there are two different friction motor styles as well (one with hubcaps and one without). Arne already showed the friction variation with the plastic canopy - that's a pretty hard to find version.
I believe the blue HK-557 came in two different box styles. I have an older box style with the blue HK-557. I believe the second, newer box style is shown above (perhaps improperly pictured with the HK-570?).
The HK-570 toy came in two different paint schemes that I'm aware of... there is a red and blue version not shown above.
Finally, I'll add that there is somewhat hard-to-find HK 559-1 friction toy. I've never seen the box, but I do have the toy: