If you have a Nokia 3310 around that is still alive (which it very well might be), it can be revitalized with a new charging port, as it is in fact a modular (or "drop-in") part that can be removed and replaced with relative ease, no soldering required.
This discovery led the modder Andrea Salvatori to see if the module could support USB-C - and that the answer is yes, as the 3310 can apparently draw the 5V supply it needs via the up-to-date port's pins.
Salvatori demonstrated that a port upgrade in the course of a 3:46 video featuring the classic phone's new USB-C replacement - which are also now available to buy for €25 via a Bento page (contact the creator for overseas availability).
The 3310 will apparently charge happily away via a modern charger and cable thereafter, and can even keep its mic as that part is removable too.
Then again, it might still be unable to make phone-calls depending on the availability of the GSM networks it needs: even the 2017 3G refresh that can be bought on Amazon for $79.99 (with a microUSB port) might have trouble in some regions.
Of course, the only other real drawback is that the 3310 will lose its 3.5mm jack to this mod.