HazardManiacPads made for HD 599, HD 598, HD 559, and others in that series will fit the PC37X. They’re actually larger pads than these in this drop here for the HD 6XX family (HD 6XX, HD 58X, HD 660 S, HD 650, HD 600).
Would you like us to look into making PC37X pads? What traits or materials would you like to see in them? Velour, like stock? Maybe our Choice Suede which is soft like the velour but sealed and increasing the bass?