SBRs you can really buy anywhere and then just put it together. There are all sorts of places to buy suppressors and they HAVE to fill out there section of the form 4 on that. As far as them filling in your part of it I never advise that do it yourself or it wont get done or done right. If you are new in the NFA game do lots of research and read lots of forms before buying anything its expensive and takes a longgggggg time. I would be happy to answer any questions you have just ask
What is the best way to get ahold of USDS? I am a newby when it comes to Class 3, and need some guidance.