* Replacement body panels: Auto parts stores (like AutoZone, Advance Auto Parts, NAPA), online retailers (like Amazon, eBay), and salvage yards will sell replacement body panels for your Avalanche. These will likely be primed, meaning they have a smooth, paintable surface already. Be sure to specify the year and model of your Avalanche when ordering.
* Plastic sheet: If you're looking to create custom parts or repair damaged areas, you can purchase smooth plastic sheets from plastics suppliers or online retailers. These will come in various thicknesses and types of plastic (ABS, polypropylene, etc.), so you'll need to research what's suitable for automotive use and painting. This requires significant skill and tools to properly shape and prepare for paint.
* Repair kits: For smaller repairs or filling in damaged areas, there are plastic repair kits available that typically include filler and primers designed to create a smooth, paintable surface.
In short, you won't find "smooth plastic for painting" pre-made and cut for an Avalanche. You need to source either replacement parts, or the material to create custom parts, and then prepare the surface for painting.
