smoke,
Try Karma Genetics Jamil Sayida. It is a fast finishing sativa Leb 27 from Esben one of the best outdoor breeders for northern climates. It is crossed with some great dutch genetics to make it more potent and should turn a violet/purple.
I'm in the similar latitude and find that Indicas suffer from mold issues if they don't finish super early. We usually have that storm around laber day that puts mold on the menu.
Last year it was 4 or 5 days of overcast light misty rain that brought on the mold. My Indicas that needed to run to Oct. 15 had to be chopped early(Oct.3-10) even though the weather was great. Especially be on the lookout in large apex buds. You can't really see what is going on in the center of the buds.