cylinder heads

So I picked up a 98 park avenue ultra for 800 bucks after I got in an accident in my regal gs. the park ave was running real rough bad misfiring with a blinking check engine light. Coolant reservoir was just barely low when I checked it. topped it off, there was brown almost plastic looking...

I have a 2015 Regal 2.4l that has had a timing chain failure resulting in bending every valve and snapping 4 rocker arms on the head. After looking at the prices for replacement parts to have a valve job done, I have decided to pursue a complete remanufactured head. My question is who have...