I'm not as optimistic as Rusty. You don't get much fruit when wind-burn takes the flowers off. No doubt they do grow some apples on Lewis, but in sheltered locations. It's like when I went to Easter Island remote in the Pacific ocean - they have a lovely sub-tropical climate, but you can't grow any fruit there (except guavas which are invasive weeds) unless you sink a crater to protect them from the wind. In fact walnuts and avocadoes grow wild, but only in places like on the interior slopes of craters (being a volcanic island with several extinct volcanoes). In other craters, bananas are successfully cultivated.

So I think your first priority must be to provide some wind protection. When I proposed growing some fruit trees in a location in my garden along a wall that is a bit of a wind tunnel, a (sadly prematurely deceased) friend of mine who was a recently qualified horticulturalist said that I should use shade-netting or similar in vertically placed frames sticking out from the wall to provide some wind shelter. (I can't say whether it worked, because the ground proved to be contaminated there and nothing except shallow-rooted weeds will grow there.)

That said, there do seem to be some varieties of apple and pear that will stand up to fairly unpleasant conditions. I visited the Organic Centre at Rossinver in Co Leitrim, which is roughly equidistant from Sligo, Donegal and Enniskillen, in the NW of Ireland near the N Ireland border. http://www.theorganiccentre.ie/ They are in a deep valley oriented to the NW at the east end of Lough Melvin that the wind whistles up, and the rain pours down, but nonetheless grew some apples and pears, and very well they grew too, with the assistance of plenty of fertiliser. They have a large orchard as well as the fruit in the display gardens. But the orchard is well protected in netted cages with shelter belts of willow and poplar, quite unlike how you see orchards in Herefordshire. Maybe they'd tell you what varieties they grow, I think they were very carefully chosen. Keeper's Nursery may also help you, they have the greatest number of varieties of any commercial nursery, and are very reputable.