Welcome to the Bunnings Workshop community. Thank you for joining us and sharing your question about Johnson Tiles.
I've spoken to my colleague at the store and searched on the Bunnings website. I've also searched directly on the Johnson tiles website. The only available size for that particular colour is 300x600 and 600x600. If the area you are covering is not so big perhaps the 300x600 might work? Using smaller tiles on a large wall tends to make it look busy. Small areas such as laundry, basin and kitchen splashbacks make smaller tiles ideal for use.