They are actually 1:3000 and I have spent quite a while searching online for them.
Looking very closely there are slight scratch marks on a few of them and I can make out a word that looks like MOMO on four of them. There are also numbers scratched into some of them, on the smaller ones some of these have been partly painted out so that the name could be written on.
During my online searches I came across a site called Mick Yarrow Miniatures selling 1:1200, 1:3000, and 1:4000 models, presumably for wargamers. Using the numbers that I could read from the models I have checked his listings of 1:3000 ships and four of the numbers,3060, 3072, 3042 and 3073 correspond to the names on these models, Yamato, New Mexico, Chitose and North Carolina. The other two that I could read do not correspond though, 3027 Brooklyn is listed as Alabama, and Kumano is marked with same number as Yamato, 3060.
I think I'll E-mail Mick Yarrow to see if he has any information on them.
Alan.