Question [Q] [HTC Desire 310] Best way to unlock?

Hi, I've been researching and I found out that apparently you cannot sim unlock a desire 310 by installing a different rom.
People recommended using a sim unlock service (like you pay for a code to unlock it), and they said that some of these services are sketchy/dodgy..

Can anyone personally recommend a good website to get a code from?
Or even a better way to do this?

(It's locked to Vodafone if that makes a difference)

Thanks