Brass & Bullets is correct, and yes they are closed on Sun & Mon. I bought 338 lap from them last summer, but I can't remember if they ordered it for me or not.
Needless to say, they are great guys in there. It'll be worth the stop.
You could also check at Snappy's in Kalispell. They are located on hwy 2 on the right if you were going to Glacier Park from Kalispell.
Have fun in town, Steve
To hunt... or not to hunt...? What a stupid question.