If I filed a form 1 for an SBR, or suppressor, do I have to do that every time I buy one? Or is it a one time fee?

It is a separate tax stamp for each individual SBR. When you apply for the SBR you have to include the serial number of the rifle, it then only applies to that firearm.

I believe it's a tax stamp for each item . I am not 100 percent sure. But yes call the gun range to make sure !

Form 1 is serial number specific.

Call the gun range to be sure.