When starting with the Osaka playership, the "Buy Ship" option is greyed-out in the Ship Broker docking screen, and it is not for a lack of funds — the option simply won't be available.

However, the option to buy a ship for one's wingmen remains available.

megas 4 Jun 2020:

This may be fixed in the 1.9 beta. Buy Ship is available for Osaka starters there.

wolfy 26 Jun 2020:

This should already be fixed, just not sure it will work in older versions of the game, which I guess apparently includes 1.8