"I don't have the means to hot-smoke"
No need to over think it, salt is not protein and it cant be burnt or over cook, it melts at over 800c!
Start a small fire in the back yard, put a perf tin pan on top of the fire,
Put a smaller tin with salt spread or stacked and put another pan equal in size to the perf one so it "captures" the smoke from the fire.
Leave untill the fire cools down so you dont burn your hands,
Done.