Did the exhaust seat stay seated? That's what usually comes out when over heated.
Briggs doesn't sell guides..
More importantly, ***for the push rods to bend, the valves KISSED the piston**
and are very likely junk. Flipping the head over and filling the combustion chamber
with fluid will tell. If leaking, the fluid will come out either / both the intake runner or exhaust.
I bought a used head from E Bay and it was EXTEMLY WARPED.
I ended up buying
brand new, with gaskets from Amazon for around $150.00
A machine shop may be able to make you one, and install but may be expensive.
A valve job would definitly be needed as well.
So, ^^ may or may not be an option..
I'd personally opt for a new head, you know everythings good and won't be doing
it again.
.