HB 367 is currently in the House Judiciary Subcommittee on Crime, Terrorism, Homeland Security, and Investigations committee which is chaired by Trey Gowdy. Contact to the various members will help move this bill to a vote although some of the committee members will probably not be amenable to persuasion on this one.
Rep Lee has a lot in common with Rep Waters (D-NonCoposMentos) but the entire membership is here. If nobody on the committee is from your district, feel free to ping Mr. Gowdy and ask him to move this bill along. Note in your correspondence that it currently has 121 co-sponsors and enjoys good popularity. If your reps aren't cosponsoring, drop them a line and ask why not.
In the Senate this is Mike Crapo's bill, S-59 and currently has 11 co sponsors. The bill has been referred to the Finance committee, chaired by Sen Orrin Hatch of Utah. The rest of the committee is here. There are several subcommittees within the Finance group and it's possible that the bill has been passed on to one of them although there is no report of such an action. To enjoy a similar level of support in the Senate, the bill would need 28 co-sponsors so if your Senator isn't a co-sponsor, drop him or her a line and encourage him to get with the program.
Letters to congress people are usually read by aides who note the issue and your position on it and little or nothing else so deathless prose isn't necessary. Write on behalf of the gun owners of America who are pleased to note the large upswing in gun ownership the previous administration brought about and would like to protect all those new gun owners from the scourge of hearing loss. The most important thing right now is to push these bills through their respective committees.