Wave washers are designed to work by spring tension, like belleville washers. By torquing a fastener with a spring-type washer to about 80% of the washer's lay-flat pressure, you allow the washer to manage the pressure under the fastener and accommodate thermal expansion and contraction, and also resist loosening from vibration. Useful for steel constructions.
Split lock washers are spring washers, but are also designed to cut into the fastener/whatever it goes into as the fastener loosens, locking the fastener in place When fully flat these won't necessarily do more than a plain washer, but if the fastener starts to loosen they will bite in.
While split locks do work better for locking, they also bite into aluminum. For that reason, I use wave washers under steel going into aluminum, like all the engine covers screws on our engines. Threadlocker works too, but every time you take a bolt out you'll have to clean it and goop it up again.
Even in non critical applications, 316 stainless is about as far from here to Texas as aluminum on the galvanic scale. I'm sure our resident Texan experimental aviator can tell you about that. Cadmium, the plating originally used on the BMW fasteners, is right next to aluminum and gives little galvanic action.
as always, YMMV and we can keep it simple--most well stocked hardware stores should have metric wave washers. Some standard sizes are pretty close to metric and can serve as substitutes.
