There are a couple +2 Fire Strike 1-hander pistols as well while levelling to fill in gaps on the 1/50/70 level requirements for Francis Gun:
Level 15: Double-Barrel Pistol. Craftable by Duncan according to Сraftsmen of Cairn.
Level 37: Hand Mortar. Blueprint to craft it if not already known can be vendor farmed from Benevald.
Level 62: Shrapnel Pistol. Blueprint to craft it if not already known can be vendor farmed from Benevald.
Level 94: Mythical Aldur’s Inquisition. Guess where the blueprint for this comes from?