I’ve got some crudely converted Voyager episodes on my PC, which I got from my UK DVDs - I slowed them down to 23.976fps and deinterlaced using Avisynth filters. Seems to play back better than the DVDs did, and corrects the pitch at the same time.
The only question I have is, whether there would be any benefit in looking for alternative sources? I’m not sure if it is now, but I know some UK channels were broadcasting the show in 1080i50. Obviously it’s an upscale, but might be a cleaner image to work from than the DVD… If you’re interested I’ll check to see if there are any broadcasting at the moment.