Uniquely Japanese pen purchase?

Hello! I’m going to Japan this year (Tokyo and Kyoto) and I’m interested in picking up a grail pen as a memento. Ideally, I’m hoping for a pen that is extremely distinctive to Japan—meaning something handmade there, or perhaps an edition or rare type that is difficult (if not impossible) to shop for online.

I’m not sure if such a thing as I describe exists! I thought I’d pose the question to the community so those with more knowledge can offer their thoughts.

Thank you very much!