Brian, ask the people that have tax stamps for ASA's Econo-Can.
The suppressor I use on my Uzi cost me only $150 (plus stamp, etc).
I can see how $200 for a stamp doesn't seem so bad when compared to the price of a big ticket item. It does keep many people out of the game when they think "you mean I have to pay two hundred just because?"
"No, it's not a silencer. This little doodad is my own invention. I call it a loudener." --Sledge Hammer