OP added picture and it appears to have mooring cleats.
Looks like there are three lift rings and some people put a mooring cleats over the top. In the picture that webbing is probably to assist getting in the boat.
I would just string a rope (or better webbing) across the two lift rings / mooring cleats. Have it hang just below the stern for something to step on. If you cannot reach the gunwale then also a short loop like in the picture to boost.
Why two over one cleat
- two cleats spreads the load - that is a relatively light weight cleat
- one cleat side of boat is curved it puts you in bad mechanical position
- side gunwale is wider - harder to reach
- side when you go to step over the ladder will swing behind the boat and be of basically no help at all
- with split you are at where the boat extends out so there is very little webbing to swing
- nice spot to swing either leg
- if you need multiple rungs I am just not sure
but if you can get in now with difficulty then most like one is all you need
For a rope ladder you are going to need to inspect the cockpit of the boat for a place to anchor. Problem is they try and keep the cockpit clear of that type of stuff as it catches rope, toes ...
You could fabricate one from rope or webbing with a couple loops. Tie it to the main and hang it off the stern.
You may be able to use a sheet cleat but when you put weight straight down it may pop the cleat and it is hard on the cleat.
Since it is a racing level is is not really designed mooring cleats or a fixed ladder.
A portable solid ladder you hang on the stern and store in the hatch may be the way to go. Steal the rigging is lot more money then steal a ladder.