We're not going to put a number here that isn't accurate for your door, because spring jobs don't price the same way twice. A single torsion spring on a standard door is a different job from a pair on a double door, and a spring that's taken a cable or a drum down with it costs more to put right than one that just snapped clean. What we can tell you is what drives the number: one spring or two, the spring's size and wind, whether anything else on the track or drum got damaged when it broke, and whether the door is standard height or something taller that needs a nonstandard spring. We'll quote the job once we've actually looked at the door and the broken spring, not over the phone from a guess. If a spring call turns up a second problem - a bent track from the door dropping, worn rollers near the end of their life - we'll tell you what's actually needed and let you decide, rather than bundling it in without asking.