Stream Video Player appears to work nicely, after some digging through the instructions.
I ended up using Riva encoder to convert the .DV file I was given to a high quality .flv file for the plugin to use.
[Update: to convert a .mov file to .flv, I used WinFF (remember that Flash output is under the websites type).
I then ran the various ffmpeg and flvmeta commands to create a preview image and to inject metadata to allow pseudo streaming / seeking on the video. It’s private on the Pegasus website, so I can’t show it here.