Since the power brakes are driven from the power steering pump, IMO if the brakes are working NORMALLY, then the PS pump is working at some level.
I assume that the steering effort is very high. Note, I remember a recent post with a PS problem. It turned out to be bad ball joints. Apparently the ball joints were binding to the point that steering effort was very high. The OP replaced the PS pump with no improvement in symptom. That is when the problem with the ball joints was found.
Remember the power assisted brakes are just like vacuum assisted brakes in that should the system fail, the brakes still work but the pedal effort is higher. I would drive it but I wouldn't let my Wife/Daughter drive it.
No leaks, the brakes work, and the car feels safe to drive. Your call.
Obvisouly, if it was leaking, I would advise no.
I did own a 94 front wheel drive GM product that the steering rack when out on. Something to do with a reed valve. The steering pulsed so much it was scarry to drive. Felt like it was tearing itself apart.
With the belt system, you don't really have the option to disonnect the PS pump and drive home without it.
Neither the PS pump or the steering rack is too difficult to change. However, I would not want to do it away from home without access to tools and such.
Tough call. Good luck.