I need to anchor a standard where there is a one-inch hole in the drywall
There is a butterfly anchor sold at most hardware/home stores.  It's a V shape with a nut and a spring at the point of the V.  It will fit into a 1" hole and then expand once pushed through the hole to a wider diameter.  You may need to drill the diameter of the hole in the standard out to accommodate the larger screw.  But these are very strong drywall anchors.