Minuteman International Plain Design Cast Iron Fireback, Small,Black

Seeing all the cracking problems, is there a warranty? Also, does Amazon carry the "large" version of the "plain"?

Does this come with feet?

How thick is the fireback? Can you set it on top of the back of the grate (I have 20" height clearance and the grate is 4" high + the 15.5" fireback)?

Is it possible to attach to the back of fireplace permanently?