>>49666156
>Is this the first recorded instance of suku merch?
late response, but nope
The Deka/BIG suku was made a few years after the suku hayday
So around 2010 or before was when the first sukusuku hakutaku plush was made. I distinctively remember pining for the giant plushie, but it was too expensive for me to rationalize importing at the time...

The small one was made before, and I own one. There was also a bunch of doujinshi comics made, and other things like handkerchiefs/washcloths and keychains. I also own a pair of boxers with sukus on them, that's one of my favorite merchandises from the time.