I guess the $89.00 doesn't sound too bad when you consider you get the vga cable, the 5v power supply, and a housing for it all. Have you tried this particular model?
I saw a board similar to yours for $33.00 plus $5.00 shipping on ebay. I found a 5v 2amp power supply cord on ebay for 7.00 shipped. The male to female DB-15 cord for $6.00 shipped. I'm assuming any DB-15 cord will work.
Either way, I would still need that female SCART to VGA cable that you have in your ebay auction. Do you have another one for sale?