[HELP] 80s movie with video inserts

[Miranda]

The special effects for this early 1980's movie were created in a video suite and then edited into the 35mm feature. As you can see, there is baked-in interlacing and awful chroma noise. Any suggestions? 

I'm not so worried about the combing, but I need to retain as much of the sharpness as possible whilst removing the chroma noise. I've tried most of the de-noise filters but a lot of the chroma noise remains with some loss of detail.

Sample clip