Here is some banners and heraldry used by the Swedish Navy historically (including Source).
Source (Swedish): http://waslingmedia.se/nationalism/sveriges-flagga-genom-historien-del-2/
Background information : Upon the new reformation and formation of the Swedish fleet, King Gustav Vasa and the government proposed this flag to be used, between 1545 - 1600.
Background information: One of the potential flags used by the Swedish Navy used between 1525 - 1580. in 1525 the Swedish Navy implemented the first waved ''banner'' with a cross however Swedish sources do not specify any information which one was the correct version used between 1525 - 1580. (several versions of this banner was used by the Swedish Navy between the period of 1525 - 80 which one is the correct one is up for discussion, examples below).
Background information : This wave pattern one was most common and used one in the Swedish Navy between 1580 - 1620. This banner was split with 7 wave pattern, similar to the ones above however without the cross.
(This one, similar to the one just about is also a potential version of the banner used between the same period however the sources are shaky on that, I.E its a potential version of the one above..)
Background information : In the middle of 1620 the 3 crowns replaced the wave patterned banner, also known as the Swedish naval warfare flag.
Background information : This one (just like above) was made 1764 and was only allowed to be carried/flown by the king and his presence on board a ship.
Might add more historically used banner and heraldry over the time.