Scizor doesn't exist in Red. As well as some moves you mentioned. I'd personally pick Nidoking, because it learns moves of many different types. The other options you listen aren't that good, or are mainly used for Normal-Type moves, which Pidgeot already does.
Woops! i have never played Pokemon Red & i forgot it has only Gen I pokemons :D
Alright then Nidoking will be best. It can learn many differnet types of moves which you already mentioned.