The last place I saw any of the standard "red" pads was Rivendell. They were being sold in sets of extremely cheap looking galvanized, nutted holders, but they were actually the ones marked with a "C" (for Campagnolo). Those were around 5mm shorter than the Mafac "4-bump" pads, but the dimensions of the tapers which slide into the holders were the same as for Mafac holders.
Bob Hanson, Albuquerque, New Mexico, USA