Check with Brownells. They have a job fair once a year.
MidwayUSA may be able to point you to a couple of smiths needing assistance, also.
But, besides having an FFL (should you keep someone's firearm for more than 24 hours), business license, Bond, insurance, Tax ID, place of business, and the other nuances, you should be good to go.
The trouble is that people are spending a lot of attention on getting new right now. When the furor of the ban subsides, repairs should start picking up.
"A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed."
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