I would research what others have used on your frame. Try
www.houseofhanson.com and
www.longarmuniversity.com
They have used long arms and frames for sale. Often they have just the machine or just the frame. When I had my smaller frame, I upgraded from a Juki to a handiquilter16. The HQ16 was a sit down machine that I put on the trolley that came with my frame. I had to take off the back handles for it to fit, but I sold it to my girlfriend when I upgraded AGAIN (see a trend here? lol). She loves it and quilts more than I do!