You don't need LC ammo or brass for an M1. Mind you, in 30 plus years, I've never seen any case lots of .30-06 ball.
If you're reloading, 150's will do, but the rifle loves 165 grain hunting bullets, 168 or 175 grain match bullets with IMR4064 or IMR4895 with regular large rifle primers. The IMR4064 gives more consistent accuracy though.
If anybody tells you to use only 150 grain bullets and 'milspec' primers, they're confused. The rifle was desgined to use .30 M1 ammo with its 174.5 grain bullet, not .30 M1 ammo with its 152 grain bullet.
For factory, Federal makes match grade ammo. Not cheap though. Otherwise, any ammo, except the Hornady 'light magnum', using a 150 to 180 grain bullets will do. Despite what you see on the Internet. Cheaper and better to reload though.