Any 120v AC to 12v DC supply will work. Use test leads to connect the positive and negative leads as appropriate.
This or similar is a good choice to keep around for various bench testing needs. Just need to strip an old 12v cig adapter to use as a test plug.
If you're blowing fuses though, it means something is shorting out, so check the wires you're going to hook up with a meter first before connecting them and make sure they aren't shorted out inside the unit.