If your interested in doing a color grow I'd recommend humboldt csi. I don't have any pics of the bud yet cuz mine are still babies. But a freind of mine did one of their mendocino purple f1's and it was absolutely gorgeous. Prettiest bud I've ever seen. You can get their seeds through seed vault of California. I'm doin a run of mendocino purple urkle right now and I'm super excited. But they have a huge variety of purps to choose from. Research humboldt csi and pick your favorite and go for it. But remember that not all purple strains turn purple every time so you might wanna pop a few beans just to make sure you find the plant your lookin for
Here's a sample pic of mendo purps from them. (Again this is NOT my bud!)
Happy growin!