The Gyoraitei is, as far as I know, a small torpedo boat. It gives of a slightly for multi-purpose than the American PT Elco, considering the two tripple 25mm mounts(granted, they sucked). It is infamous among modellers and drawers for being very hard to get good sources. I know a guy who made a lego modell of it a while ago, who noted the lack of proper sources...:
http://mocpages.com/moc.php/254985
I've played BS:P a few times myself, even though it's riddled with historical errors(
), though I agree it can be great fun in itself.