Kondo made a few posts on Saizensen's twitter yesterday (https://twitter.com/st_saizensen) about various stuff that you could buy here (https://suzuri.jp/drawline/products). They don't support international shipping but you could still make order through some proxy service.
Personally I couldn't pass on that F9 T-shirt.
Ohh, cool! What colour T-shirt did you get? I'm going to think about it, but I'm leaning towards black.
Thanks for letting us know!
Yeah, I got the black one. I mean, nothing besides the white and black meddled that well with the image imo.