Hi Mike - thanks for the reply (it's Bob, BTW).
Yes - it's not an efficient design by any means. I need the LED to pulse at the bottom of the oscillator cycle, which is why I've done it this way. The efficient way with the LED in series with the collector will flash on at the oscillator peaks. I've tried it both ways and it seems to make very little difference to the total current draw of the circuit.
The 330k takes care of limiting current from the oscillator through the base-emitter, but I was wondering about possible discharge from the 4u7. I strongly suspect it's not really an issue, but I'm not much of the "if it don't smoke and it works, play on" school. That's the main issue really.
After a bit more breadboarding I see I could accomplish what I want with a 2N3906 PNP instead (see attached) and have the load in series with the collector (flashing on in oscillator the troughs). Needs an extra 22k to pull the base up and the 2n3906 seems to need more current to the base than the 2n2222a (had to swap the 330k down to 100-150k). The extra draw from the oscillator makes it run noticably faster, which is not so good. Haven't properly checked, but I think the oscillator feedthrough is a bit stronger too - that would be more of a problem. Again, total current draw difference is very small. I guess the 4u7 *really* won't be an issue with this design.
I'd like to go with the 2n2222a solution (for now) as I've already made a PCB. If the cap discharging isn't going to stress it...