Call Norm. The Prod/1720T is close to a discovery, but gauge in slightly different location, and will inlet for what trigger pack you want and guard. OK, I see Boyds is selling direct on the disco now. You will need to plug and fill gauge hole and redrill, plus some work for a Mrod trigger pack. Disco gauge is about 1/2" further toward the rear than Prod/1720T. Boyd's has 5 stocks available, but not the Blaster. Most of these look like they would be too long for a standard 1720T/Prod airtube, except for the Evo or Cuda. I'd be interested in what a 1720T look like in a cuda.