Both the item description and Subetalodge say it's in the Cash Shop, but I can't find it under any of the categories. Am I overlooking it or did it get taken out? (Yes, I do see that a few people are selling it in their shops and I can just buy it for sP, but eh, I like having options)

I think they retired it from the shop for the moment.

Ah, okay. I suspected that was the case, but wasn't completely sure. Thanks for your help!

Yep they retired it and it's only available on Black Friday