As far as I know, portepees on SS daggers were only allowed for SS-SD officers and that the date authorizing this was after the M1936 was being worn. That means portepees should be found on chained daggers. The exact way of tying them on daggers is debated among collectors. They were standard Heer portepees. If anyone has better info or dates, please post
My opinion is that far more M1936 daggers have portepees now than during the Third Reich.
If you want to see M1933 daggers with them, visit eBay, Gunbroker, 321 Militaria, etc