I used to be a customer of superbrightleds.com, and had absolutely no complaints on their products, but now the same products can be had for 1/5th the price on ebay and amazon, so I started buying from there with similar results.

Just search 12v LED on either Amazon or ebay and you will find A LOT of options for a very reasonable price.

Google SuperBrightLeds they have the underwater lights that mount on the transom as well. They are more money but the ones I would get are $100 a piece. I have seen those under water lights for transome for a rediculous amount of money for a light. I would love to see what justifies the $1100 price tag on some of these lights.