1998 Toyota Camry RACK AND PINION STEERING LEAK

I took my Camry into a mechanic, but I'm new to the area and don't have one I really trust. I'd like a second opinion.
The Problem: I left my car sitting for a week (a month ago) & when I went to drive it again all the power steering fluid had leaked out. I re-filled it, but after 4 days or so, it would leak out again. I used leak sealing power steering fluid as a temp fix and kept a close eye on it to keep it filled. I took it in to an import auto repair shop and he looked under the hood. He said it was leaking from my rack and pinion steering and that it would need to be replaced. He quoted (w/ labor) $950 using new parts or $550 w/ remanufacturered parts. It seemed a little steep. I thought it may need a new pump or o-ring valve or something to that affect. But replacing the whole steering seems much worse. The car runs fine when the fluid is full. Not sure if I want to invest that much. Any thoughts?