You might try these. All were accurate 10 years ago and probably still are.
237.9000 Coast Guard Operations Secondary air-to-air SAR
242.6500 Coast Guard SAR datum marker beacon
250.9500 Coast Guard East Coast Maritime Defense shp/shr/mob
275.1000 Coast Guard SAR datum marker beacon
277.8000 Coast Guard Ship/aircraft use nationwide (shared)
282.8000 Coast Guard SAR on-scene primary frequency air/gnd
326.1500 Coast Guard Air-to-ground primary
345.0000 Coast Guard Operations Primary
379.0500 Coast Guard Air-to-ground secondary
381.7000 Coast Guard Nationwide SAR, LE, Intel & MDZ ops
381.8000 Coast Guard Nationwide SAR, LE, Intel & MDZ ops
383.9000 Coast Guard Nationwide SAR, LE, Intel & MDZ ops