This is an original painting created to illustrate the 2nd book in the series for Knight Books; at least, that's the title that Fred has for it, but to his knowledge it was never used for that title; possibly another (?) but we can't find this image on a book in the series online, so it may be a variant with limited distribution or another title published 1988-1992.  Painted in acrylic on illustation board, 18.5" x 11.5" and comes signed.   Fred produced several covers for books in this series, all of them equally appealing; you have your pick of any that remain available!