For this scenario, a new FEDERAL law states you're allowed 6 handguns, but only one per cartridge. No duplicates. Conversion kits not allowed. Spare parts must be bought with the gun. No spare parts after that. Reloading not allowed. Serial number designated to specific cartridge. IE; a .357 better not be found with .38's in it.
Calibers to choose from:
.22
.32
.380
9x19 mm
.38 Special
.357 Magnum
.40
10mm
.41 Magnum
.44 Special
.44 Magnum
.45 acp
.45 Colt
I see some folks are choosing a gun for each caliber, but not restricting it to 6 total. I don't know what my choices are yet, so this is quite interesting.
I wanted this to be different from similar threads that get sidetracked with words like "sexy" and "classic."
Also I tried to address the "why" of the question, since that certainly dictates my answers in these types of threads. (Just starting out, from what I already own, etc.) also, to eliminate the "I'd get a 1911 and shoot 27 cartridges with assorted top ends" response.
If it's not worth your time, then please don't post a response.
Since you put the spare parts thing on there that in itself to me is going to limit my semi automatic choices to a minimum. Also with the designated cartridge per gun it removes guns like the judge and the governor or the S&W 610 from my choices, other wise I would most certainly add the S&W Governor and the 610 to my list since the Governor can fire three different rounds out of the same gun and the 610 two. So on to my list and since this is pretend, I'll pretend that money is no object.
1. Taurus Tracker 992 Revolver in 22LR even though it comes with a 22 Mag cylinder also. This would be used for small game in a survival situation since in most states you can not use centerfire ammo on small game.
2. Magnum Research Desert Eagle Mark XIX Semi Automatic Pistol .50 AE 6" Barrel with at least two spare mags minimum. I chose this round because it is a big and powerful enough round to take out any big game on this continent with good shot placement without having the recoil of the 500 S&W.
3. This will probably be my last semi on this list even though I prefer them to revolvers. Ruger P944 40 cal. S&W. I chose this because I love this gun. It is accurate and built like a tank so it will hold up better for the long term over a polymer framed gun. This is also my carry gun at this time till I can afford a smaller pistol. I already have two spare mags for it though I really want to get some new grips for it soon.
4. Ruger GP100 Double-Action Revolver .357 Magnum 4.20" Barrel 6 Rounds Rubber Grips Blued Finish. This would be my backup home defense gun that would stay in arms reach at night.
5.Taurus 905 Revolver 9mm Luger 2" Barrel with some aftermarket grips and a lifetime supply of moon clips. This would be my backup carry gun. Why? Easy to get ammo in a small enough package to be a CCW gun without having to worry about to many extra parts.
6.Ruger Super Redhawk Double-Action Revolver .44 Remington Magnum 7-1/2" Barrel 6 Rounds Hogue Rubber Monogrips Satin Stainless Steel Finish. This would be the backup for the 50AE if it ever happened down for some reason. I'd have at least two speed loaders for all the revolvers that used them. I would have chosen the .454 in this gun since it would be closer to but more powerful than the 50AE than the 44 Rem Mag is, but finding ammo for it would be even harder to find than the 50AE is nice I do see the 50AE on the shelves at the LGS now and then along with the 44 Rem Mags, but never do I see .454 on the shelves.
Just a note but if money was no object and this actually did happen I would have me an self sufficient island built in international waters and start my own firearms and component manufacturing business on the island and invite allot of you guys and gal to move there.