My kids have home assignments to practice calligraphy at the beginning of the year. I bought dedicated papers for it at Seiyu. It cost 203 yen ($1.69 €1.41).
Plastic string = 108 yen ($0.90 €0.75)
I bought a roll of plastic string for 108 yen ($0.90 €0.75) at a 100 yen shop.