What I own now; I'd have to take my Mosin. I'm almost out of x39, and I still have 400 rounds of x54R.
The only pistol I presently own is a blackpowder
.44, though, if I had time to go over and borrow one, I could get a 9mm from my father, or a .22 revolver because I have plenty of .22.
(My present loadout of guns is a Mosin, an unconverted Saiga, a blackpowder .44 and an old model 60. I mostly shoot my fathers and grandfather's guns, they've got larger collections than I.)
Yes, I'm low on ammunition and guns, but, I've got more important things to do than buy guns, like buy food and gas.
What I intend to own within the next year;
A yugo M70 underfolder with a couple 30 rounders and a Glock 19 with some 33 rounders.
Edit, Fantasy load, a M16A2 with an M203, some buckshot and some HE shells, with a Glock 18 as a side arm. Might as well go all the way with the sidearm...