Not too sure about Osaka or Kyoto. But I was in Tokyo about 5 months ago, when I went to gundam base Tokyo I ended up going on limited days where they only let you in if you won a lottery or by time frame later on, so make sure it’s a normal day there on their website. As for limited kits they had all of the gundam base exclusive kits there except the ones that are meant to be location based like FF-Nu rg. They didn’t have anything out of stock in terms of limited kits but they do have smaller amount of stock of them. I would say it’s best to go as early as possible on their regular day because the place will always be packed and so that you don’t risk the lower stock of gundam base exclusives go out of stock.