If you must have GM factory parts you can go to any GM dealer such as Gosch Chevrolet
If i were you,i probably consider O'Reilly's auto parts.
Go to General Mlotors, but if you can purchase the part yourself and have someone put it on cause its cheaper. The dealer is always higher and the cost is higher and then they want to find something else wrong to get in your pocket. I use to work for Cormier Chev.
Chevrolet parts
They have a parts section. .call them
Go to Chevy dealer for parts
Depending on what you need, start with your nearest auto parts storr.
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