At the time (Feb'23), the command history says $24.75 for 5 populated boards, including custom/duties to France. No memory how that translated into euros at the time.
Yes, they did all the SMD stuff (passives, the gate, the small switch), I bought the actual connectors for both sides from Mouser IIRC. That's the most expensive part - connectors are never cheap :-/
BTW license on that is CC BY-SA 4.0, so apart from "credit where credit is due", you can do whatever, including reselling excess inventory if you decide to make some for yourself. You also have the full schematics/pcb files (Kicad) if you want do double-check things or do them differently.