Your going to have to go up the mast to get the bulbs out so you know what size they are. If you want to change them to LED's go to Autozone, Pep Boys, Advance Auto Parts, etc, and find the same bulb in LED form. All the lights on your boat are basically low wattage DC fog lights from cars, so there are a whole mess of options when it comes to replacing/upgrading them.
However, you should look at why you want to change them in the first place. LED's are expensive and your probably going to sped at least $20.00 per light to get them changed over. Why go through this trouble when regular bulbs are $5.00? If power consumption is a concern buy another battery or get a charger to maintain your current battery while on shore power. That will cost as much as the LED's and will benefit the rest of the boat as a whole. If your concerned about the longevity of LED's vs. incandescent bulbs then consider that you can buy 4 incandescent bulbs for the price of one LED; plus incandescent bulbs last pretty long so chances are you'll be waiting at least a decade before the price evens out.
I'd honestly just stay with the incandescent bulbs and upgrade the infrastructure of my power system if I was you. What ever you do, don't change the interior cabin lights to LED's. A buddy of mine did that on his H30 and it completely ruined the feel of his interior. The bleached white light made everything seem cold and inhospitable.