You can get one shipped for around 30O US$ from yakumo at
http://assemblergames.com/l/threads/...shipped.44220/
I bought mine from him and have been happy ever since.
Towards the end of that thread there's lot of info, but in short ditch the component altogether and go HDMI obviously.
I confirm the Saturn switcharoo hi/lo res is very annoying for the Mini, hopefully they'll fix it with a new fw release.
Finally the lack of a sync stripper on the input is kind of glaring and can give you trouble for some consoles (SMS, MD, NeoGeo AES).