Sir/Madam,
I have experience of building websites with membership requirements, plus http-pseudo-streaming using Flash. For example of video "streaming", please see www.outofspacethemovie.co.uk.
I could produce an HTML-based or Flash-based website and provide video "streaming" via a Flash-based video player on your site, while safeguarding your video files (to stop visitors downloading the file by linking to them directly).
Regards,
Chris