Comment by robinhouston

Be careful! There's a whole world of mechanical puzzles out there, and it can get very expensive and start to take over your life.

Here's an assortment of links to places where you can buy interesting puzzles. This isn't exhaustive of course: it's just a few places that came to mind.

https://www.puzzlemaster.ca/

https://puzzleparadise.net/

https://www.pelikanpuzzles.eu/

https://twobrassmonkeys.com/

https://www.etsy.com/shop/PuzzleguyStore