Obviously the best person to ask is the account manager at the agency. As far as I have come to understand the advertised jobs is that the client companies don't want to go to the expense of type rating a pilot, or don't have enough time to go through the whole conversion course, but just want to base check someone, and get them on line. That is why experience of the particular type, and variant is specified and required. The account manger doesn't have much discretion to interpret the client's requirements unless they don't get enough applicants that satisfy the specified requirement so convince the client to relax some of the requirements. Even if you have several hundred hours on ie the 737 EFIS you will not be considered for a job on the NG series. But try to build up some sort of dialogue with the account managers, and they may be able to get you in somewhere that you might not get to if they didn't know you a bit.