Hi David and all,
David - based on what I think I can see on your pics (thanks Ed for posting), you may indeed have a transtion HK from one variation to the next. While not unique - they do indicate HK manufacturing, so my thanks for posting! As well, the pictures do show the MAG release very well, which stands out on how the fire-blue release (right side) differs from the rest of the frame blue.
I'd be very interested in some pictures of the toggle stamps, most especially on the transitional HK.
David - simply outstanding HKs from what I can see. Congratualtions!!!!
My Best Always,
John D.