The schematic of the resonant energy transfer is in Fig. 8 of the following document 
https://o-esd.etf.bg.ac.rs/forgejo/dragan.olcan/O-ESD/raw/branch/main/Documents/O-ESD-02.pdf

The capacitor is printed on PCB, while all available components (trafos, reed relays, etc.) are being tested (see ./4-HV/Trafos and ./6-Switch for details).