Roller Shade Mount End Cover/Cap

I picked up the low-cost roller shade/window covering from Home Depot which does not come with a valance. The brand was "StyleWell Cut-to-Size Cordless Room Darkening Vinyl Roller Shades" model UVRD6G7378AA sku 1004459997 internet 309076207. Sometimes they are listed as "unbranded" but they typically all use the same mounting bracket which is approximately 46mm x 31mm.