Encountered something strange with the LM358 oscillator prototype. I could only get one 'old' stock LM358 (DIP) to oscillate, newer LM258s (DIP) and SOIC lm358s were no go.
From looking at other OPA oscillators it appears that much higher resistances than that used in the sim may be required which started to cause BOM issues again. Anyway, I decided to keep it simple by dropping the OPA and using a PNP to make an RC oscillator.
That worked out ok and I am getting 11V no load and 8V with a 1K load.
Oscillator & charge pump fit on 1 sq in of PCB using smd parts.
EDIT:
Did some bench testing with the opto today. It's emitter follower drive capability requires a < 470K base - emitter load to reduce switch off latency to manageable sizes.
The FET gate-source needed an additional 0.1uf cap to dampen drain-gate parasitic capacitance noise (to < Vth) as the drain is subject to a lot of hi energy ringing from the outbound connection.
This requires the push pull drive to switch the capacitive load within a few microsecs.