Need to replace cam shaft, how much is too much?

My '96 Geo Metro is making another knocking sound. I have replaced 4 rocker arms over the past year, and am now being told that the cam shaft is worn and will need to be replaced. I have an overhead cam, so it will need 8 rocker arms.

What would be a reasonable price to pay for this. The car runs great otherwise. It has new tires, new radiator, battery and the maintenance is kept up. I love the gas mileage and don't really want to have to get another car, but I don't want to put more into the car than it would be worth.

It has 115,000 miles on it now. Anyone have any suggestions?

replace the whole head. Check out www.car-part.com. Replacing a camshaft with a new one can be fatal to your head. If your cam bearing journals are worn, and you stick a new cam in it, it could flop around, and completely sieze. Check out www.car-part.com for a used head, and have it rebuilt. It'll be worth it.

might also want to check your oil pressure and when you pull head off check the oil passage to head and the restrictor valve. these heads usually don't fail this way unless there is a problem