Power Steering Question

[eastcoastcivil]

I have a 67 C10 and power steering was installed by th PO. The steering box is leaking fluid from the top so I assume the seal is done. Are these seals still available or do I have to replace the whole box? I was told not to drive it because I could burn out the pump but the resevoir is full, its only leaking out of the steering box. Is it possible to unhook the belt for now so I could still drive it with manual steering or should I just leave it parked until I fix the problem? Thanks