I see a cap and T-shirt from NetBSD website,here is the link:
Nice cap and sweatshirt,I want one
unicorn check these too https://www.cafepress.com/netbsd
As Jay has linked above, please use cafepress and if feasible choose the TNF support option. This will help the NetBSD project.
Sorry,I can't open cafepress.com in my country
FreeWear.org are also donating to TNF, our financial logs show as much :)