I am not finding anythnig in Arlington proper, however, there is a great place in nearby Poughkeepsie (about 1.7 miles away) called Stamell Stringed Instruments. They make and sell and specialize in violins, violas, cellos, and basses as well as provide rental services and repairs/tune-up's. There is also Vincitore's Hudson Valley Piano Center which rents and sells pre-owned pianos. There is D & M Music in nearby Pleasant Valley, NY (about 3.8 miles away) which sells, rents and services band and orchestral instruments. And finally, there is Alto Music of Dutchess County in nearby Wappinger Falls, NY (about 6.5 miles away) which is pretty much comprehensive in its offerings.