I built 4*XHP70.2 light from Convoy L6. Mine uses 2 batteries in series, but if you manage to find a single cell tube for it and use 3V 70.3’s or high enough power boost driver it might be worth a try.
Similar driver topography with the Freeman’s Sofirn SP36 boost driver should be good canditate. With search you should find the thread, where he presents that driver.