Gun shops cater for what their customers demand and the demand for FAC air rifles is tiny compared with sub 12 ft/lbers. Go ask your dealer how many he has sold this week of each.
A demanding customer is a pain in the arse. You will find it isn't cost effective to go converting everything. FAC guns always are sought after but the right person has to find it.
You can spend thousands and still miss a barn door or spend just enough and enjoy yourself. If you haven't got the talent to start with a million pound won't fix it. Whippet, Russell, a few bang sticks and a flat cap. http://www.smart-tech1st.co.uk