If it's going to be used for defense, take it to a gunsmith.
It's not worth the risk to save a few bucks.
Even if you take it to a gunsmith, test it with 100+ rounds of your defensive ammunition. Gunsmiths screw up too, and some gunsmiths are better than others. Don't skimp on testing a gun out with your defensive ammo of choice. It's not worth the risk to save a few bucks.