I have got my navigation lights from Piplers of Poole. Neat little LED lumps which are designed for RIBS but I think they will be just fine for me. They should draw under 2W between them.
I have fitted the stern light without much trouble. The side lights will have to wait until I have painted the booms gallow support and screwed it in place. Then I can put one at each end.
I have wired them in temporarily to check that the basic idea works and it does. I shall feel much safer sailing around in the gloaming, which often happens to me when I am looking for good anchorage in the evening.