Master cylinder for clutch

Hey guys...'07 4 cylinder 5-speed here. My clutch pedal began sticking to the floor recently and I believe the problem is the seal is going bad on the piston allowing it to blow through rather than move fluid in the final third of its travel. Everything works great as long as I don't push the clutch pedal any further than roughly 2/3 of its travel. Luckily, that's plenty enough to fully disengage the clutch, but I'm having to use the bypass switch on the lower dash to avoid pushing the clutch pedal to the floor to start the truck. Can anyone confirm my diagnosis or comment on a similar experience? Also, what am I looking at in terms of work/cost to replace the clutch master cylinder? Any input would be greatly appreciated.