Good grief.
22TCM doesn't exactly grow on trees. Neither does 10mm. "Finding" that ammo just doesn't happen. You won't be carrying a hard case with friggin' gadgets, either, if you have to "bug out". You'll be carrying as little as possible, and what you carry has to work as is and to as much double/triple duty as possible. The Serbian lessons on this are relevant and stark.
For the SHTF piece, a modified cylinder GP100 .357 that will then take .357s, .38 Specials, .38 Colts, 9x23, 9x21, .38Super, and .380 is a much more realistic BUG.
But, please don't let reality get in the way of fantasy.
I very well realize that 22TCM and 10mm ammo are relatively scarce, even in the best of times. Which is exactly why I am thinking that having extra uppers or fitted barrels in 9mm, 22LR, 45 ACP would be important additions.
BACK on topic.... being something of a speed freak regarding guns and velocity, I am surprised that I have not yet owned a 38 Super. That will hopefully be rectified in the not too distant future.
