They kinda look Imari in style, but that would be a guess. Most likely with the words made in japan stamped on them would place them Post 40's. Condition looks really good on the bottom to be older then that. Maybe look around this site for the marks
http://www.gbouvier.com/Seal/s_seal.htm I believe KC turned me on this site, or DB, can't remember, but a wonderful site for looking for Asian marks. They are very wonderful looking vases and the looks will hold most the value. How big are they, this can make some difference too.