I will be doing that this summer for the Luger 30 project. I use an extension ladder which works well since the deck is a different height at different parts of the boat. I had thought of the hand rails at the top especially after removing all of the hardware and hand rails from the deck there is not much to hold on to way up there.Yeah, but Crazy Dave used to be a boat dealer.
If it was me, I'd just get an extension ladder with a fitting to hook it to the toe rail..
When I'm in transit the ladder is strapped to the frame of the trailer. You can even rig some handles at the top to help you on and off.
My cat used to be able to scale it going up but would ask to be carried down. Since his recent stroke he even has a difficult time getting up on the sofa but then I have a difficult time getting up off the sofa. Whata pair.