Switching the AA battery with a D-cell. I have changed one of the 100nF ceramic capacitor to a 10nF version. Thus the frequency is now 10Hz instead of 1Hz. So, it can still blink for 10 years. This Energizer Max D-cell has a shelf life of 10 years.
Need to find a housing for it.
The 4 screws holding the circuit board to the battery holder are 1.6mm glasses/watch screws.
I have also pulled away the LED so that it may be afixed somewhere else in its future housing.