We used dreamcatchers for a long time with DS8 -- first it was a crocheted blanket that his godmother made him, really loose weave with a variegated yarn that had sparkly bits, and we called it "Dreamcatcher". Then we had various real dreamcatchers that hung in his room. He also drew pictures of himself beating the monsters in fights, and hung those over his bed.
I never used Monster Spray, but I always liked the idea.
We didn't have the "wrap up in the sheet" thing, but that got me wondering, perhaps a sleeping bag might help? You can get those sleep-sack ones that zip into a hoodie type thing at the top, and he might feel really safe in one of those.
For the ordinary sleep troubles that don't involve monsters, Melatonin works wonders.
