Just email SMSL and explain there is no option where you live for the upgrade so wish to do it yourself. The instructions make no sense though so whether it's worth it I don't know. I was already moving mine on to be honest so didn't invest much time in it.
They will send you an update tool if you pester them enough, their instructions for the update make no sense though. I have sold my m500 and returned my sh-9, the way this has been handled is terrible. I won't touch anything by SMSL again.
FYI hifi-express seems to be an semi/non official...
I have a mint M500 with the update kit for sale if anyone is interested. I won't be splitting these, I just want as sale as have changed DAC. Located in UK.
https://www.head-fi.org/classifieds/smsl-m500-v2-mint-with-update-cable-tool.7305/
Of those that have mentioned they have updated m500 devices, can anyone confirm if they have done this themselves and if so where you got the firmware from please?