The early sensors have leads and are sided, the newer ones just have a socket and can be either LH or RH. Front and rear are obviously not interchangeable front to rear on both types
You could have had mine, have had them for years but never fitted them. I am looking at putting in some classic two tone snail type horns that sound like a macho car :)
Make sure you seal the underside of the rivnuts with silicone, a major area of water ingress, mainly over the pollen filters. Put a dab on the new screws too, they sometimes split open, I replaced all of mine, I bought a big pack of black self...
I have mentioned many times that the plastic rivnuts for the self tappers (as per Keith) loose their foam seals and let copious amounts of water in. Just pop them out and dab silicone on the flange, when you put the screws back in give them a dab...