Last year I have bought 2 long sleeved tops at Costco and was very happy about them. They are fitted, made of Australian merino wool but very fine and lightweight (I would not think they are wool if not for the label), not itchy, machine washable and came in different colors. I got teal and plum ones and wore them to death last year. They last much better than any cotton, rayon or any other type I had before: do not stretch, do not pill and still look like new!
Anyway I was in Costco yesterday and they have them again! I have seen black, blue, turquiose, tomato red and plum and they come in crew and V neck styles. Oh, and the price is $15! Of course I have bought three right away in black, red and blue. Blue is going back as I do not like the shade on me, but I am happy with red and black!