Does anyone know how to change a rubber gasket (or if there even is on to change) on Panerai 01314 crown?

Hi all, I was applying lubricant to the O ring on my Panerai as it had been a while and I intend to go to the coast for some diving soon. I ordered a black band for it besides the stock green, I think it will look nicer and will post picks when it arrives, I can't dive with the calf skin one in salt water… I definitely like that more than rubber. Do I need to change and o ring for the crown? I didn't see how.