Do eBrake cables need to be replaced if they are not broken ?

Probably not needed. The only reason they would go bad is if water got inside the metal sheath and rotted them from the inside. Abrasions to the outer sheath are not critical, just not pretty.

Thanks Mark. I was thinking they might stretch over the years and be too long

If they should stretch, there are a couple of adjusting nuts inside the engine compartment that will allow you to take up the slack. My cables looked like hell when I took them off last summer but they still worked OK. I never had to adjust them. I replaced them with new ones just to make things look better.

I'm at or near the end of the possible adjustment

If they are that far a long with out much adjustment, go ahead and get some new ones. Try autohausaz.com. Under $35 each, buy each side and the shipping is free.