I think either the Carcarno or the De Lisle is the best sniper rifle. I like the Carcano because of its 16x zoom (when upgraded) and it's bolt action system, which I prefer to semi automatics in the sniper class. I like the De Lisle because it is always silenced (and it's bolt action) although it does have a pretty woeful zoom. (Only 8x when fully upgraded.)
The M1911 is my favourite pistol. I bring silenced ammo with me and don't need too much because I hardly ever use the pistols in my loadouts. I use the M1911 because of its 2 shot kill at close range and its semi automatic nature, which I find preferable over the Welrod's bolt action mechanism.