When shopping for flashlights; go to home stores such as Lowes and Home Depot; often you will find more economical brands and special deals. While there be sure and check out the hand tools; anything that doesn’t require electricity.
In a “systems offline” scenario hand tools can be your best friend. In regions where woods are plentiful a few wood working tools can turn natural resources into everything from shelter to furniture and other tools.
A good way to prep and save money is to make the items you need. You not only improve your sufficiency skills but will save money on the store bought equivalent. A good source for hand tools is garage or estate sales.
Another significant cost savings technique is to repurpose items. Adapt containers from one use to another; from durable throw away packaging to “close out” merchandise which can live again with a new purpose and usually at a bargain price. Be sure to check for quality, since some of these products are often cheaply made. Adapt and improvise as needed.
Anything that requires a replenishing supply to make it work should be carefully considered. What might work for a short time; say a week or so might not be a good idea if the situation turns into months on end.