Are Finger Guns Period?

At our Baronial Investiture, I had convinced my peeps that our Barony's new "gang sign" should be finger guns. Someone told me that finger guns aren't period because pistols aren't period. "Really? You think," I responded, "finger guns weren't used until someone invented the pistol? I say to you that pistols were invented because of the existence of finger guns."

So, is there any evidence of finger guns pre-dating pistols?

Take a gander at this image of Marpesia and Lampedo (BNF Fr. 599, fol. 12). A clearly defined finger gun from the end of the 15th century.

Here we see another finger gun from 1440, from Le Champion des Dames, » par « MARTIN LE FRANC, prevost de l'église de Lausane.

Here we see Roberte from the 1564 "Roberte the Deuyll: A Metrical Romance" with a rare double-barreled finger gun.

Here is another 15th century image, although I was not able to track down the source.

Here is Christine de Pisan (1363?) with an over-the-breast finger gun.

Here is a silver arm reliquary of Saint George, the rootinest tootinest saint who ever lived. This is dated to the 13th century and can be found at Conques, at the Trésor De L'Eglise Sainte-Foy

Here is a 14th century Irish reliquary of St. Patrick held at Ulster Museum. 

And, finally, a 14th century Swiss Reliquary Arm of St. Valentine in the now familiar pose. You can visit this item at the New York Met.

So, it would appear that finger guns were relatively common in the 13th, 14th and 15th centuries. The word pistol didn't appear in the French language until around 1550 and in English around 1570. The first firearm small enough for us to call a pistol didn't appear until 1605. So, I am confident in saying that the pistol was invented due to the common practice of finger guns.