Reddit mentions of Aged Lumos/Nox Light Switch Cover (Custom) (Aged Patina)

Light switch cover (I also need this)

Have your front door area decorated as Platform 9¾

Have different rooms as House common rooms

Laminate or otherwise reinforce this and place in your front garden

Cushion covers

Looking at this stuff is making me want it all.

For my last birthday, my brother got me this cool lumos light switch. There are lots of options for similar products online and it's a project that you could probably easily make yourself with supplies from a craft/hardware store.

I had a friend give me a wall transfer once that she made with her cricut. It looked something like this and it's been on my wall for ages. Same friend also made me a couple pillows with the same machine that had Dumbledore quotes on them. Imagine this but with "Happiness can be found even in the darkest of places..." on it.

I've also given out an "After Harry Potter" set of books before. For those who read Harry Potter and think "what now?" I'm sure this could be catered to the receiver, but the set I gave my friend had Miss Peregrine's Home for Peculiar Children, Lev Grossman's The Magicians, a printed and spiral bound set of Pottermore writings (or the ones that were available at the time), and The Unofficial Harry Potter Cookbook. I think I had one or two more, it was a couple years ago.

I also handmade a pair of Luna's radish earrings for a friend once. I followed a tutorial online and it was surprisingly easy - just required a pair of earrings, some wire, and a few beads and they looked great.

I guess it all depends on what kind of gift you want to give her. There is a Harry Potter application for just about everything. If your girlfriend doesn't have a lot of the standard merchandise already, you might try just checking out the local bookstore. With the release of Cursed Child, most bookstores in my area now have entire tables dedicated to Harry Potter gear. Last time I was at a Barnes and Noble I walked out with a Marauder's Map blanket. I've been sorely tempted by that 3D Hogwart's puzzle a time or two as well. And when I went on the WB studio tour, I got this really cool wand necklace. It comes in an Ollivander's box, though it is a bit pricey.

Good luck. Happy birthday to the gf!