I think they're around $100 but try a parts place like http://www.partsamerica.com or http://www.gmpartsdirect.com/ You can just enter the part number and it will come up.
hw much does an 81 buick skylark weigh?
4169
About 2500 pounds.
Try http://www.gmpartsdirect.com/
Around 3100-3200 lbs
Around 2400-2500 lbs
It's around 2800 pounds.
Around 3400-3600 lbs
Try http://www.cars.com/ You'll get a good idea of the cost.
I have a 1995 Skylark and that repair is at least $500.00 but it's worth it. The engine runs great now.
We just replaced our entire exhaust system in a 97 skylark custom 4 cylinder 2.4. It cost us almost $700.
Maybe $100 tops....