Stay away from federal brass (even the match stuff).Federal is notorious for having the primer pockets loosen up even after just one firing.
I had the best success using Winchester cases in my M14/M1A/M305s........
If you want Lake City brass, make sure you get Lake City Match brass. Standard Lake City brass usually is machine gun brass.
Some years of Lake City Match brass (early to mid 1990s) will have knurling around the base of the case. This was because M852 match ammunition was not authorized for combat use and the knurling was done so you could tell the difference.
Some will say don't use the knurled brass as the knurling weakens the case head, and others will say it is a myth.
I have shot knurled M852 Lake City Match case out of my bolt gun and custom M14 type rifles with no problems.
M118 and M852 Lake City Match cases will have "Match" stamped on the base. M118LR (Current issue) with have "LR" stamped on the base.
Military brass is thicker and softer then commercial brass, therefore slightly less case volume so you have to decrease your loads slightyl
As for your Mom bringing you brass out of the U.S, there is a sh*tload of paperwork she will have to do to legally do this. Export/Import permits will have to be applied for, and there can be lengthy waits.Paperwork,cost of permits, and general hassle is why a lot of U.S. firearms businesses/companies will not ship to Canada.