You do not need an 07 FFL if you take an existing complete functional firearm and just replace parts, with NO milling or machining. It can be done by a CA 01 FFL.
So, yes, an off-roster handgun can be sent to you and you can change the parts (barrel & magazine) while in CA.
FFL Transfer/Special Order Dealer since 1993.
Net-FFL list maintainer.
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