Don't be put off.
In my opinion which, I've formed over many years in sales, I believe people are willing to travel if its for the right thing. May I suggest you advertise on B&O which, I've found a wonderful site for selling.
My last RIB went via B&O to a guy in London who drove to Abersoch to pick it up having paid £500 deposit without even setting eyes on her. Thats a 14 hour round trip!!!
It's all in how you sell it ! If you put 2 lines of blerb about size, engine and trailer you're not going to stimulate anyone however, fill a sheet of A4 telling a story about the boat and you'll make the phone ring.
I've just placed an ad on B&O for my Medline, take a look at that for some ideas. Further, I'd go as far as to advise the buyer that if they're keen and make a credible offer, you'll knock the price of their ferry ticket of the asking price (inflated of course to cover this). With this in mind you're rib has to be immaculate ! What you also have to bare in mind is that, there's not a lot of RIBs for sale like yours, yes plenty of dive type ribs but not many with the Delux advantages that some folks are after. Good Luck.
Buy it & Use it, then sell it and buy something bigger