I believe the 700 series motors have a 30mm mounting pattern, hence the special mount that Kershaw sells for his 700HOs. You can modify the stock mount, or just buy the mount from kershaw, or even make your own easily enough. As for motor options:
http://banebots.com/pc/MOTOR-BRUSH/M2-RS775-144
1205kv, ideal for slower speeds if ran on 4s lipo.