Nuts with spiral lock washers won't stay tight. The lock washers lose temper and tension when heat cycled. Loctite won't work, either. I've donated several nuts to the road that way. Might work for a week until you get the real thing, and might not. My best "other source" solution was to use flat washers, loctite, and flange nuts with serrations on the flange.

Not responsible for advice not taken...