Dunstone won the Canadian Junior Curling Championships in 2013. He represented Canada at the 2013 World Junior Curling Championships, where he won the bronze medal. He was unable to defend his championship at the 2014 Canadian Juniors after losing in the finals of the Manitoba Canola Juniors to Braden Calvert. The next time he would represent Manitoba was in 2016, after winning the 2016 Manitoba Canola Juniors. This earned the Dunstone rink a spot in the 2016 Canadian Juniors where he won his second title after defeating Northern Ontario 11-4 in the final, and represented Canada at the 2016 World Junior Curling Championships, winning a bronze medal.