I guess it's a short question..
Is it worth it to gather parts and build my own VZ61, or one of it's variants? If so, which would be recommended? For my own personal use, of course. I'm not an FFL holder.
The first question is the easy one. Of course it would be worth it! You'd be in the middle of a project for a while. A great excuse for frequent visits to gun shows, sporting goods stores, etc... And with Christmas coming up it's easy to make a Christmas list.
Which variant depends on what use you intend to make of it.