Oh shit... your power supply question.|
From what I understand, the power tip you need is Maplin part number AR28F, AKA Power Tip R. This is just a part that attaches to the end of a universal power supply and fits the US SNES.
In terms of the spec of the actual power supply - you just need to get one which can output the specs printed on the console or I think slightly over. You obviously don't want to go mental and feed it ten times the ampage or anything like that, but I believe giving something a little too much voltage or ampage, especially in low amounts like this, doesn't do much harm. It's making sure it's DC and the polarity is the right way around that's important (polarity = the way you affix the power tip). Maybe another EGer can verify this?
21 consoles, 5 handhelds, 2 PCs, 1 Mac and about 700 games from the past 30 years. Every major manufacturer and developer represented. Still a fanboy for disagreeing with you.