The statement is misleading. Good luck finding a new model. Civilian purchases of new full automatic firearms were stopped in 1986. The remaining and dwindling pool of pre-86 weapons is the reason it costs $12,000 to $16000 for rifles which only ran $1500 or less in other circles where the legal purchase is not so constrained (military and law enforcemnt). An AK-47 is a $300 rifle in the rest of the world, but is worth well over 10 times that here because of the legal restrictions, provided it is transferable.
These artificially high prices limit the ownership of full auto for law abiding people, while those who care naught for laws can obtain smuggled weapons more cheaply, or import their own with other contraband.
While looking at weapons online, I ran across a Reising Model 50 .45 submachine gun for $5,295 here -
http://www.autoweapons.com/products/products.html
I believe the model 50 is a select fire.