Iwent looking for the smallest good arcade stick, and I found TheTboxShop's $160 FS-Mini, a 3D-printed design intended for fighting games but surely good for all of them. It comes in thirty color options, with stick or all-button designs, and there are several variants to pick from at the creator's store.
3d Printed Mini fightstick, printed in PLA. Although they are pretty durable, they cannot stand high temperature (above ~130°F/~55°C) or it will start warping/melting. Try not to leave them in your car in a very hot day, but do reach out if you need replacements for anything!
Spotted via this review on YouTube, by NihongoGamer: 00:00/29:28 10
Less expensive is the $40 Leverless Controller, only 11mm thick, which can be color-customized with a widget; you could stuff it a sleeve with

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