Jannik,
Yes I meant from 737-200 to 737-800. To my knowledge they will only pay for the conversion cost and not the full type rating.
I am only a student pilot and not involved with Ryanair, but this news is fairly common in the industry and instructors and Multi-IR students in our school in the process of starting MCC and the "long, arduous, CV sending" process are feeding this info back to us.
It's also been in the news in the last 6 months
Your suggestion of doing a 737 Classic rating then converting to the NG is a good one in that it gives you a great competitive advantage over lesser qualified applicants, especially if you have the financial means to go for it.
Good luck with whatever you decide!
Simon.