Before I started this trip back in Aug I tore out and rebuilt my small slide and replaced the floor and some of the framing.
I had no trouble with the standard staples you get from the hardware store but they really need to be STAINLESS STEEL.
These worked fine. And they are plenty strong if not stronger than the originals I pulled out.
Dont worry too much about using exactly what the MFG used. They have lot of different reasons for using specific types of hardware and one of the biggest factors is time...how long it takes to install. Strength is not always their first concern.
Mine has held just fine and I expect will easily go another 10 years.