If your Super Nintendo is dead, it is probably easily repaired. This posting has been sitting in my Blogger queue for 3 months. I'm planning to add pictures, but for now, I want to get at least something up.
Disclaimer : You do this at your own risk. If your house burns down as a result of these attempted repairs, it's not my fault.
One has to admire the engineering that goes into these consoles. They are built like tanks. I recently reassembled a Nintendo 64 from parts. Works like a champ.
On to the repairs...
Problem 1 : Broken power jack
Soultion 1 : First, make sure that the conductors in the broken jack are not shorted together. Remove the circuit board. Solder wires to the circuit board at the location where the power jack connects to the board. Purchase a replacement jack from Radio Shack. If you use part number xxx-xxxx, you will be able to use a -9v Sony power brick. Mount the new jack on the corner of the case nearest the power jack.
Problem 2 : Lost/broken power supply. Can't find a -10 volt power supply
Solution 2 : If the plug is ok, cut the cable off the power supply, and patch on a new one. Any 9 volt supply of at least 500 ma will work. It turns out that the -10v input is regulated down to 5 volts anyway, so 9 works as well as 10. Be sure to wire the polarity correctly.
On future repairs, I'm planning to install a bridge rectifier between the power jack and circuit board. Then the polarity is irrelevant.
Problem 3 : Power light does not come on (probably related to problems 1 and/or 2)
Solution 3 : The internal fuse is probably blown. The fuse is soldered to the circuit board. Remove and replace with a fuseholder and fuse. Or use a fuse with pigtail and solder it in directly.
If the cart slot is damaged, I don't know what to tell you. Cleverly, the connector can be unplugged from the main circuit board, making connector replacement easy. Assuming you can find one.