When you say 1:1 or 1:2 are you saying one INCH to one FOOT or one INCH to two FOOT, or did you actually mean full or double/half size? It doesn't really make sense to ask for a full OR half size unless you really are asking for a MODEL. I suspect you were saying MODEL sizes. There are lots of plans available, fairly inexpensive for a model, but a full size plane is a huge commitment, and few WW-I planes could carry a pilot at half size (plus I can't imagine why anyone would want a double size plane).
If you are looking for MODEL plans some of us may be able to help you.