I made few runes for my projects in substance painter.
You can download it here for free https://gum.co/JnknI
Reference for runes found over google, and made by this person https://elabeth.deviantart.com/art/Runes-35265500
There are two types one is clear white stamp one has gradient, which can give interesting output when used as height stamp.
Quality 2048 x 2048 16bit Tiff file with transparency using ZIP compression.
Can also be used in quixel.