Umutcan
I only have this one. If I had more than one Iβd ship you one.
You can get it here. A little expensive. But, a little bit goes to supporting Flarum.
https://www.redbubble.com/i/hoodie/Flarum-Logo-by-flarum/63141071.O6XP1
I also ordered mine at the beginning of the COVID pandemic and so it took a super long time to get to me. But, I bet they are shipping faster now.