944S Head Problems

[Pierce]

I have an '88 944S that has a damaged head. The tensioner post is broken off, the cam chain is broken and I am sure some valves are bent (I haven't taken the head off yet).
The first thing you think of is that the belt broke and caused the damage,but that is not the case here. The belt is fine - something happened to the head.
It seems that used and rebuilt 16 valve heads are scarce as hens teeth and when you one it may be as high as $2600 with your old head in exchange.
I don't want this happening again.
Any solutions or suggestions???