f-250 clutch stuck on floor

I own a 2000 f-250, 4x4, 7.3L diesel, 175,000 mi., recently while pulling to a stop light the engine stalled out on me, I then noticed the clutch was stuck on the floor and had to pull it up with my hand. I drove it home, and it continued to get stuck so it hasn't been driven since. A friend tells me that i may be able to get away with replacing a slave cylinder located on my firewall. Seeing is how money is most definitely an issue, I would be concerned with finding then most inexpensive repair possible. All advice would be greatly appreciated. Thank you