Ken, fwiw. If you want a simple flasher/pulser unit, then use an LM3909, 8 pin LED driver/flasher chip. ~$3.00.
See attached circuit. Should work O.K. It will flash continuously but you can vary the brightness.
If needed, you might try changing the value, (more/less microfarads but not by much), of the capacitor to vary the flash rate.
HTH a bit.
L.