If its the bellows shaped item, replacing it is possible, but wont stop the leak or even slow it down.
If the leak is from one of the hydraulic hoses (both about 3/4" diameter), then replacing it may stop the leak. Its not uncommon for the hydraulic hoses to begin to leak. The high pressure hose handles up to 800 psi when you are maneuvering into a parking spot. The low pressure hose only handles about 30-40 psi of oil; that might be 150 degrees hot.
If anyone ever worked on the rack, they may not have gotten the nuts tightened up where the hydraulic lines connect to to the steering rack. This can also be a source of leaks. Its a miserable area to reach, from either below or above the engine.
I had a car that used power steering fluid steadily, but it took me some time to find where it was leaking from. The high pressure hose had a pinhole in it, and when the engine was running and someone turned the steering wheel - a thin stream of p.s. fluid would spray from the passenger side of the engine compartment, all the way onto the driver's side suspension parts! It got everything behind the engine soaked with the fluid. With the engine stopped there was ZERO sign of p.s. fluid oozing from that hose! That was on a front wheel drive Dodge.