I have not found any store that carries the Garmin chargers in stock. The fastest solution is to find an option on Amazon. I have picked up a few extra and keep one in the laptop bag, in the car and anywhere else I am likely to possibly need one.

These do look interesting. A great way to use existing cables and portable enough to always have around.

https://www.amazon.com/Compatible-Replacement-Charging-Forerunner-Approach/dp/B094Y3SXT3/

https://www.amazon.com/XHZ-Compatible-Replacement-Charging-Forerunner/dp/B09DCP9ZDN/