A couple of options. Walmart has a cheap desklamp socket that Edge users have been cannibalizing and then using a 10W coralife PC bulb on. They zip tie that onto the light bar and use that. Pretty decent spread but it's another cord and might not be the safest option if you aren't careful as it's a full 120 volts. You can look into some of the LED replacement lamps with the MR11 sockets. MR11 sockets are what the stock edge unit comes with unless they've changed the lighting around since I bought mine. You'll want the surface mount LEDs for this and not the 5mm ones. You can get some of the MR16 LED replacement lamps for this as well. You then either need to modify the sockets on the lightbar or buy replacement sockets which are cheap. If you go the LED or bulb replacement route do NOT exceed the 10W per bulb rating on the power supply. Users on other forums have done so and blown out the power supply. Of the options, the LED replacement lamps are probably the easiest/safest to start with just because you don't have a 120 volt path inches away from open water. Given the salt water aspect, make sure to hit the LED bulbs with a clear spray sealer as I've seen photos of ones that corroded.
You can also go all out and replace the lighting with a custom heatsink and Cree LED setup, but that's going to run some money and falls firmly into the DIY range so you're looking at a project involving time and $$$. But the few I've seen are very nice.
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