The labor for this is the big cost.
TOB is <$100 and a whole clutch kit (which includes the TOB) is only like $200-300. The rest is labor. Considering you're probably looking at $600 either way, it's definitely worth putting a clutch & pressure plate in if you're planning on the long term.
If TOB is going, it can destroy the snout of the transmission case, which is a more expensive repair. It usually doesn't, so it may be worth it to risk that... but you don't want to be the 1 in 10.