For a small, sport type vessel, nobody is going to care or even probably notice.
However, if you'd like to fly your own flag and wish to be polite about it, here is an portion copied from a Canadian nautical guide a lot of yachting clubs use. It's written from the perspective of a Canadian boat visiting another country but can easily be reversed.
1.8 Courtesy flags
When you visit foreign waters, your boat should display the civil flag of
the country you are visiting whenever your Canadian flag is displayed.
(Shown is the U.S. ensign.) Your courtesy flag is not to be larger than
the national flag.
If your vessel is mastless, it should wear this “courtesy flag” at the bow,
in lieu of a squadron or club burgee, or on a starboard antenna strong
enough to support it. If your vessel has one or more masts, display it
single-hoisted at the outboard signal halyard of the main star-board
spreader. Move any flag normally flown there to the inboard starboard
halyard or, if your boat has only one halyard per side, to the port
spreader halyard. Try to learn the correct procedure for the country you
are entering. For example, in some countries it is customary to fly the
courtesy flag only after the quarantine flag (see next page) has been
secured. Do not fly a foreign courtesy flag after you have returned to
Canadian waters. It is not to be used as a badge of accomplishment for
having cruised to another country.
When a foreign guest is aboard, you may display the flag of the guest’s
country from the bow staff or outboard port spreader. Should more than
one such guest flag be appropriate, wear them (on spreader halyards
from port to starboard in the alphabetical order of their countries names
in the English language.)