HomeStreet Bank, a bit player in the jumbo mortgage-backed security market, wants a bigger role and has recently sought assessments from rating services and is working to expand its jumbo originations. Moody's Investors Service announced last week that HomeStreet received an "average" rating as an originator of jumbos. The Northwest bank also has jumbo MBS servicer ratings from Fitch Ratings and Moody's. Terri Silver, a vice president of investor relations and corporate communications ...