IMO, The best thing to do is cut the elevator off and rehinge. However somthing that would work vevy well would be to monocoat hinge the entire surface. You could do this without removeing the elevator. With the monocoat hinge, plus your 3 remaning c/a hinges it will last a very, very long time. I would decrease the elevator throw just a touch to releve the stress on your remaning c/a hinges. I've done this befor with no problems.

Darren