Video with travelling flicker when deinterlaced

[spiritgumm]

Have dvd videos of home made transfers of tv show episode films. Looks like someone used a mirror box (projected the films into a mirror box and videotaped them with a vhs camera). I want to convert the video to another format (ie mkv). IVTC (tfm/tdecimate) would work, but there are blended fields so it would look better deinterlaced. However, doing that reveals two horizontal bands (alternating dark and light area) that travel upscreen. It's visible if you step thru the video with separatefields, or try to deinterlace. Btw, the bands are not visible doing IVTC. Reminiscent of filming a monitor, but not as prominent. Is there a filter or method to mitigate this side effect?

EDIT I didn't find a deflicker or chroma fix, but bobbing with a deinterlacer and unblending with Srestore set to 24 fps eliminated the problem.