maybe just try to resize, they are not big differences.
Resizing wouldn't work for all of them, unless I make them quite a bit bigger than they are. So 164 x 48 would need to be 256 x 128 to avoid it being cropped, but would leave some blank space around the image.
Is the rule just that the proportions can be divided by each other equally? I see some textures are 256 x 256 and 512 x 512, but also 256 x64.