Check your local dollar stores and other places selling extremely cheap merchandise before buying flickering LEDs online. Inexpensive battery-powered flickering tealights and
taper candles can often be found where the flickering
effect is all inside the
LED, with the plastic part largely holding the batteries and guiding the
power to the
LED. Bonus: the tealights come with a CR2032 battery.
One idea which occurred to me, depending on how strict your
theatre fire code is, would be to have a small CR2032 flickering light in the palm of the actress'
hand, and the "match" be a small steel rod which is struck against a spark-producing material, such as a flint surface. This way the "match" doesn't have to contain
the light source or even the battery, and the act of cupping the
hand around the match squeezes the
switch to light the flickering
LED light, which then illuminates the actress'
face. As the match "goes out", the actress simply stops squeezing the
switch, and the flickering
LED goes out.