There's Sellrain in Maine but he's taking 2021 off from new work. There's also MacPherson Firearms in NH and
@daekken had a Bulgarian AKS-74 built by them recently. There are a couple other small time builders, but Sellrain and MacPherson are the two I'd suggest.
Having an AK built for you makes sense when you want something that isn't commercially available. If you're into collecting specific AK variants, then hiring a builder versus building yourself becomes a time-money equation - how much is your time and effort worth versus how much are you willing to pay. Plus, if you have a very expensive and irreplaceable kit, let's say a PLO Soviet AKM kit, or a very nice milled gun kit, it might be something you wouldn't want to do yourself. Or, another example is if you want something that would require more advanced work, like say an adjustable gas block.
Realize that a builder is going to charge somewhere between $500 and $800 currently. And many of the quality AK builders aren't taking new work or only take very certain kinds of work. So, the AK-63F kits sold by AOA are going to be $820 plus let's say $800 for the builder plus shipping and other incidental costs plus the cost of a receiver and other parts, like say 922(r) parts because gunsmith-builders typically require customers' rifles to conform to 922(r).
Is it worth $1620 plus the cost of a receiver and other ancillary costs for you? That's a question you and only you can answer.