Yup; but without trading, you can only choose one - just like you did at the start of the game. Serebii will explain on how to get them:
> The third & final batch of Starters you will find are the Pokémon whom trainers start with when they begin the journey in Hoenn. In Heart Gold & Soul Silver, these Pokémon are obtained by visiting Steven Stone in Silph Co. in Saffron City after you have defeated Red. He will compliment you, ask you what colour stone you'd pick and then provide you one of these Pokémon based on the colour. As with all starters, they will be at Level 5.