Gary M - What name / spelling is given on any travel documents you have been given either from the Holiday Company or Ryan Air. Email Receipts, itineraries etc.
If you received "documents" upon booking, or on paying if you did not pay at the same time that you booked, then generally an airline would have expected you to check that all the names were correct etc. You would then have a few days grace to call them if some of the spellings were wrong etc. The airline would then make the amendments without any charge. Perhaps a bit more complicated when the travel company may have made the airline bookings on your behalf, but the principle still applies. Beyond that they would charge you a fee, and not necessarily a simple low admin fee.
There is reasonable probability that RyanAir will try and charge you for correcting the name now, but clearly this is so obviously a mistake and an easy one to make at that, they should just sort it out without any hassle. But they are RyanAir, with a business model centered on product de-bundling and increasing margins by charging extra for EVERYTHING.
EDIT sorry the stuff above is certainly not trying or intending to cause you any further stress. As you say it is only a space, this is why I said if you can check in then do so, transfer the problem to them and don't worry about it.