This is what I found; I don't know if the axle would fit your hubs..
http://www.amazon.com/dp/B001CC9GE6/...SIN=B001CC9GE6
I also found the tandem axles you were looking at.
http://www.sjscycles.co.uk/suzue-tan...s¤cy=usd Apparently the old Suzue tandem axle had a habit of bending but these new ones are better. The old axle could very well have bent was replaced with the wrong axle.