These are the labels that I now use in many of the clothes that I sew.
The red mark is made with a Japanese hanko that I bought via ebay from an American living in Japan. (It is my name, if that wasn’t obvious.) Clothing size is printed using a metal stamp set that I think is intended to be used for stamping metal jewelry. My set is like this but also came with numbers.
I know I could have custom labels woven (um, if I really wanted 1,000 of them), but I really like the look of a hand-stamped label, it reminds me of old-school typewriters.