I use to recommended an AK74 as a good SHTF weapon. The 5.45 rounds are effective and cheap. The gun is easily handle by another. The Bulgarian model I have is built as rugged as a AK47 and at the time it was CHEAP. I brought it two years ago $349.00 with three magazines. The same rifle is now sell on sell for $599.00. All I can add if you haven’t brought your weapon yet, you better by NOW!
If you're operating on a tight budget, a good alternative in .223 (or 7.62x39) is a Saiga .223 with a 16" barrel. It is a sporter version rifle made in the same factory as the AK-47. It is very tough and reliable. You can buy a lot of nice American after market parts and accessories, including 30 rd mags, tactical stocks, handrails, etc. The basic rifle can be bought new for about $300.
One caution though. If you choose to buy 30 round mags it changes it to an "assault rifle" and you then must change your installed parts configuration. This can be done very simply. If you buy US made 30 round mags (readily available), you will need to add at least one more major American made part (a TAPCO or other US made tactical stock or handrail will do). This is because of the crazy BATFE regs governing content of "assault weapons".
If you choose foreign made magazines, you will have to change out not one more part but 4 more parts. This further conversion can be done with readily available parts, but it will add cost and you may not want to bother or make the additional investment but it is possible.
Still, using US made mags, you can be totally outfitted quite easily for well under $500, including scope or electronic sight, and you won't need to practice your gunsmithing skills. All you'll need is your credit card and a screwdriver.