Toro ring deck needed

I don't see it available any where..
 
If your slightly mechanically inclined, I'd remove what's left, take it to a hefty vise and go at it with 
a 5 lb ball peen hammer...
 
You'd be surprised how much you can straighten it out as it's not terribly thick..
Take your time...
 
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You can trace the deck (area concerned) on card board and then transfer to steel.
 
Use a Sawzall (or similar) to trim it to shape.
It would take some time but do-able.  
 
You could also bring your "template" to someone that works with metal to make one...
 
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