Youre better off buying a new rack.
A worn outer rack seal, inner rack seal, and/or rack bushing o-ring within the racks main body will cause one or both bellows to leak, especially when the bellow itself is torn, obviously. There is also a pinion seal buried at the bottom of the steering shaft. Fluid can find its way into the breather connecting both bellows if either the pinion seal or the inner rack seal is worn.
Either way youre looking at a rebuild. But if the inner surfaces of the rack are scored, replacing the seals is a waste of time and money.