The rate does seem a bit steep. Do you have ACRP certification? If so, they offer their members discounted rates. For my S-corp, I believe I pay around $550 per year for Errors and Omissions Insurance. This is a discount from the regular, non-member fee, which I believe is somewhere around $600-650 per year. By the way, the quote you received may not be someone trying to "fleece" you. Most companies I initially contacted did not know anything about insuring CRA businesses, so the quotes I received varied widely, presumably based on other "similar" occupations.
Here is the direct contact for the insurer I use (via ACRP):
William G.F. Sullivan
CM&F Group, Inc.
99 Hudson Street, 12th Fl.
New York, NY 10013