Can you be more specific? What do you mean by breaking the keel? Crack, keel fall off? ???????
Do you have the centerboard or fixed keel?
Really need to be more specific if you want someone to help...
Also, try the 6.9 class association website for advice too.
S2 no longer makes sailboats. So anything you do would be custom, but depending upon what you mean by "break" it could be rebuilt.