Using a pour over with water from a kli shlishi (irui kli sheini, actually) might be muttar according to some (certainly not all), but I don’t think it would taste very good.
Starbucks Via is excellent, and less than 50¢ per cup if you buy it in Costco when they have a “coupon”. You should also use irui kli sheini for that, but it’s very good.