That's great that the vendor is willing to polish out the spots for you. With regard to Renaissance wax, sure it will work. I used to use it on firearms all the time before I found something even better. There's certainly nothing wrong with using it. However, any very light coat of oil, whether organic or synthetic, will work on carbon steel to prevent rust. For example, I protect knives that I might use for food prep, deer skinning, etc. in the woods with pure virgin olive oil and that works fine. The only trick, regardless of the lubricant used, is to make sure that the blade is absolutely dry before it is applied.