I picked up a pack of LED lights from Lowes today. $10 for 5. They use replaceable button batteries that are easily accessible via a screw on back that also has an adhesive pad, are 16 lumens, and about the diameter of a quarter.
I think they'll work great in small dark places in the boat.
I've put a number of adhesive puck lights on my 23, although somewhat larger that use three AAA batteries. They really help and are much more effective than the stock lights that came with the boat. Like the size of those that you've shown, but don't really care for the "button" batteries, seems like they always develop a film and have to be cleaned with alcohol regularly. I did install hardwired (to the 12 volt panel) red night vision lights the size of yours in both cockpit lockers and low in the cabin, so I can see without losing my vision at night.
Hmm . . . don't like wafer batteries either, but waterproof is an offset . . . thanx for the heads-up.
I put a string of LED lights all the way around the cockpit hidden under the overhang. I added a dimmer and am very happy with it. They are 12v - connected to the battery. There is plenty of light for reading anywhere at full power, and nice effect when dimmed. They are indoor/outdoor so very durable and the string has adhesive on the back side so I just pressed them in place - but totally invisible.
I have thought about installing string lights like that. Good to hear they work well.
I meant all around the cabin - they are inside.
Yes, behind the teak that hangs down along the cabin top sides.