So, there are plenty of ways to shop and compare. The CPR facemasks are sold through facilities that teach CPR and certain medical suppliers and they will be far less expensive through the latter. Sterile water is used to cleanse or flush wounds. Tweezers are used to extract small embedded objects such as splinters and stingers. Cold packs can also be used in controlling bleeding and swelling, as cold constricts blood vessels.
Emergency blanket is to cover the victim in caring for shock.
Disposable gloves and CPR masks are forms of universal precautions to guard against exposure to infectious diseases. Small zip lock bags are for the collection of fluids that may help in diagnosing a victims condition. From here it is only a matter of putting everything together in a way that works for you. Anything that has not been opened will have a long shelf life. Instant cold packs can require periodic replacement if you live in regions of variable weather.