How about... crayons?? I love Crayolas.
Ahh, crayolas, the smell of my childhood. Which is weird because they don't sell them anymore here. Crayola as a brand is widely available, but no more wax crayons, only some jumbo ones for little kids. That's why I had a friend of my mother bring me a 64c box from the US

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I never use them, but that wasn't the point anyway

Last year I had to order a 10 count box of notebook because they are unavailable in stores, it was the only way to get them, so I first made sure I could sell back a few to friends, I still have 4 or 5 of them unused.
They're Rhodia Dot paper, they're not lined or with a grid but with dots in a faint color every O.5cm, the perfect fit for me who use it for technical sketches but also to write or draw, and at least half the price of Moleskine (who doesn't have dot paper anyway).
As a smaller notebook I use a small Moleskine, the kind with 32 pages and the last 16 are detachable. In goes everything I might need to keep track of for a short period of time, drawing ideas, list...
I came to understand that fountain pens are not as widely available and used everywhere else but in France?
Here we get our first fountain pen when we enter middle school (around 10/11 y/old), that's when you know you're a big kid! (some primary school teacher let you use one unless you have terrible handwriting or smudge it all over).
And maybe 75% of students will use one until the end of their studies.
Speaking of not available, the bane of my existence is that I was in Japan for a couple of months, found great pens ad mechanical pencils and wonderfull office supplies that you just cannot find elsewhere

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At least in the US you can order from jetpens.com, but the shipping is a bit too much for me in Europe.
Japan seems to also be the only country where they know about 0.3mm 2B pencil leads, which is a shame, a shame I tell you!