Can I fly it at night?

I have a 1941 Chief with lights on it. There's one light on
each wingtip and one on the top of the fin. There's no
anticollision light/strobe or landing light. There are
wires from the 3 position lights to the cockpit, where they
end. The engine has no alternator or generator and never
has had one. There's no battery, battery compartment,
starter or electrical system. I do have a portable sealed
lead acid battery that I charge between flights to power a
radio and intercom.

There's nothing in the paperwork about "day VFR only" and
there's no AFM or even any POH.

I've looked at 91.209 and 91.205 (c). I've got position
lights, I won't be operating for hire, so I suppose a
landing light is not legally required. I suppose a larger
battery would be an adequate source of electrical energy for
short flights. Can I fly at night if I install an
anticollision light? Anyone want to comment on what I need
to legally fly at night for short local flights? Does
anyone think the disconnected lights have made the aircraft
legally unairworthy for the last 65 years? Does anyone know
how these were originally powered (Dry cells?)

Thanks for any information.