thank you for the responses that were useful. I figured it would fall into the SBR cateogory but I didn't know if all I had to do was fill out the form 1 and send the $200.
I figured there was more paperwork than that involved.
also, is the $200 tax a one time thing for this specific weapon?
i.e. $80 rifle + $200 tax stamp = $280 historical firearm for the rest of my life.