make a DIY canvas, these minimalist 90s Nickelodeon posters are awesome. Unfortunately not for sale, but that's where the touch of your hand becomes valuable.
This Friends poster is great! It lists all the lessons the show taught you! Right now it's on sale for $6! Easy and cheap.
90s themed T-shirt is fabulous, but only the best 90s fans will know exactly what these shirts are when they see them: Legends of the Hidden Temple. They're only $18!
90s DVD sets- also great. You could go with anything from Boy Meets World to Saved By the Bell to anything Nickelodeon. If you want to go the Nick route, there's a website dedicated to it, with sets from 30-40$.
doesn't wanna pretend like they're from Bayside? This sweatshirt is suitable for guys and girls, and is only $34.
Singstar for the 90s. It's necessary and only $29.
15th Anniversary Edition of the Tamagachi was recently released, is in color, and a whopping $130. Didn't they used to be real cheap?
HANDHELD SUPER NINTENDO. It's totally worth every penny of the $85, and you can stock them up with a few games from eBay for anywhere from about $2-30.
As for stocking stuffers, I'd recommend things like scrunchies, Beanie Babies, and pogs [that you can find on eBay] that have a dopeness that will never fade.