Mike; Pin tubes are easiest. But spacer them up off the pans with 3/32nds inch square tubing, to give you more "meat" between them and the lower body sills.
That bracket does look like the BWA bracket, that I believe REH sold. The narrow bracket from Chicagoland works just as well if you are using piano wire rails.
For those looking for a vintage narrow bracket, Electric Dreams has the old Ruskit brackets for 16Ds.