Buddy and I made DIY teeth for his CUT.
We went to a truck spring shop and obtained scraps of HD (3/4") spring stock and proceeded to fabricate a tooth bar.
Well that was 4-5 years ago and just today I observed his DIY tooth bar was holding up well and barely showing wear.(and his terrain is rock infested)
I make some teeth with a variety of junk steel, garage door track and rebar were the most of it. It sure looks like trash, and I have since gotten my hands on some "bars" of AR burn table drop, but I have had no need to redo it. Its all holding good. Even soft steel is quite a bit harder than gravel.
Trailer leaf springs would work really well since they are hardened and some are really thick. A local shop gave me a set a couple days ago that I planned to someday make knives out of them. Just a little sharpening on the point like a chisel plow tooth would work and they are already curved slightly.