Straight repair usually wins
On a torsion spring snap or a cable that's jumped the drum, a straight repair almost always wins - parts are cheap relative to that income, and a working door doesn't need replacing just because it broke once. Where the math shifts is a door itself from the original build: with a median year-built of 1957 here, a fair number of garages still carry the one-piece or early sectional doors and the side-mounted torsion hardware that came with houses from that decade.