Pontiac Firebird 1967-2002 - Need site recommendations to purchase metal work parts 67 Firebird

Can you tell me where there are reasonable sites to purchase rear quarter panels, trunk pan for a 67 Firebird. I came across this on Ebay, is this a good deal?

Thanks

http://www.ebay.com/itm/1967-Firebird-Rear-Quarter-Panel-Skin-Pair-LH-Left-Hand-RH-Right-Hand-New-/390377867685?pt=Motors_Car_Truck_Parts_Accessories&fits=Year%3A1967%7CModel%3AFirebird&hash=item5ae45589a5&vxp=mtr

I know Classic Industries sells them but I don't know if they are GM originals or reproductions.

I'd go with either GM authorized sheet metal "Goodmark", sold through Summit Racing:

http://www.summitracing.com/search/Department/Exterior-Accessories/Brand/Goodmark/?keyword=1967+firebird

or AMD (Auto Metal Direct) I've heard good things about them:

https://www.autometaldirect.com/?option=com_netlinkbridge&view=makemodelyear&Itemid=111&prod_cat=&selectedcat=&type=items&selectedmake=Pontiac&selectedmodel=Firebird&level1=52&level2=595&level3=1967