Hi Doc,
It would help, but probably won't do a 100% job. Meaning a 1:1 match. Even if it did, it would only be keeping the radio safe from a bad SWR but your radiated signal would be greatly lessened. MURS in 151 and 154mhz, is many several mhz away from a tuned 2 meter beam, and the as-is SWR up there would probably be well over 3:1. So the ability to radiate all of the radio's power would be significantly cut back. But...if you can get an acceptable match with a tuner, it will work some, and as long as you're not looking to transmit over a goodly distance, it might work.
If you're serious about MURS use, it would be better to get a second antenna and tune it for those frequencies. You'll be resonant then, and won't need a tuner at all.
good luck!