Arranging Raff's Sinfonietta for wind quintet would indeed be a bit of a challenge. In my opinion it can't be done without losing a lot of the original composition. Ditto for the octet and even the sextet. I have done some arranging myself and in my experience the best you can choose are pieces for piano or piano duet. Theodore Gouvy has composed a lot of sonates and other pieces for piano duet and some of them are probably suitable to arrange for wind quintet.