Steel Plate Shim Spacers, 4" x 4" - 1/8", 3/16", 1/4", 1/2" - Pack of 14! | eBay
Amazon.com: Moyishi 9 Pcs Metal Strips Metal Shim Stock Metal Sheet Metal Shims Gap Filler Trim Strip 12'' Length x 0.02'' Thickness (Width 0.78'') : Industrial & Scientific