The wing-bolt is designed to shear if the wing pivots on it. I have never had one break yet. You will have difficulty finding an alternative because it is M7.
I have put my jupiter through some fairly violent manouvres, and nothing has broken yet (except wearing out the rudder hinges, and busting a couple of undercarriadge legs). I did'nt like the pull-pull rudder setup, so I used a solid carbon rod on one side only, which may have helped wear out the rudder hinges.
I would estimate that I have put in about 200 flights on the plane, and I now use it for teaching my son to fly.

If you are doing the undercart mod, then all you need to do is bend a piece of piano wire into a flattened U shape and secure one leg of the U to each plastic leg with a tie wrap at the top and bottom. The plastic legs will always break only where they meet the fuselage, and although they are only a fiver a pair, Ripmax quite often doesn't have them in stock - and in fact its cheaper to get spares sent direct from modelfly in Italy. Keep an eye on the fuel tank stopper screw, mine became loose after a couple of years and started weeping.

How does it go with the .65 4-stroke, it sounds like fun ?