Before Switch, before smartphones, even before Game Boy, Nintendo released a line of handheld games (and watches) under the Game & Watch brand, and for Mario's 35th birthday last year, we got a special-edition one that runs the NES version of Super Mario Bros. Nintendo stopped production at the end of March, but you can still find these. In fact, they're cheaper than ever from multiple retailers.
The Super Mario Bros. Game & Watch comes with Super Mario Bros., Super Mario Bros. 2 (the Lost Levels one, not the turnips one), and some other fun functionality like a Mario-themed clock. Its tiny little screen is backlit and it charges by USB-C, so it's both a collectible and something you might actually play.
At $40, the Mario Game & Watch is $10 cheaper than usual. While it's currently out of stock at Amazon, you are still able to order at this price. We're not sure how long that'll be the case, though. It's also available for $40 at Best Buy; the price will show up once it's in your cart.