URL of (Japanese) garage kit circlesNote that all the circles I list have something to do with Girls und Panzer because I am interested in only GuP kits.
Ploy-Toys - They sell in events/festival only. Their kits are virtually impossible to get outside of Japan. However, GK sells them. They are recasts though.
Amie-Grand - Sells on their website and have a shop on Amazon Japan.
Bronze Circus - I've seen their kits listed on websites but I am not generally interested in their kits. Mandrake online shop often carries some of their kits.
Maid-san - Like Poly-Toys, they seem to sell in events only.