All those aftermarket grips come from the same Chinese factories, there are only 2 versions of the grip, one with 2 screws in the middle (has plastic perts) and one with 3 screws (has metal parts). Buy the one with 3 screws,
it's more solid, has a metal plate in it for the mounting on a tripod and is made better over the 2 screws version. I bought mine for 41 euro (incl shipping) = 54 usd = 52 AUD. Don't let yourself fooled if they have a "brand" it all comes from the same manufacturers.
Unless you buy a genuine one.
I don't go out in the rain so I have no need for weather sealing. It does the job for me and no problems with it.
You want to buy this version: Example: