You don't even need that many honor scores or that high of an average if you can help promote and sell the product and provide intellgent and useful feedback. Before I signed, my highest ever book was 219, but I had been running successful shops for years, make money at some notable tourneys and had a large knowledge base at which to provide quality product feedback.

I had only shot 1 300 prior to signing.

That being said, staff positions are severely limited, so competition for them can be pretty stiff, so don't get dejected if you don't make the cut. Even just applying can build your network and help you long term.