The only other car I can find that ran under the 750 cc supercharged limit in F1 was a Giaur (Giannini-Urania) that competed in the 1954 Rome GP non-Championship Formula One race. Driven by Berardo Taraschi, it (#34) was listed in 11th place after dropping out on the 5th lap. It "finished" ahead of 4 cars; three that dropped out earlier and one that was a DNS. On paper, it seems to have much more potential than the (Deutsch-Bonnet) DB Panhard. There were one or two other 750 cc supercharged F1 cars built (Gleed-MG for instance) but I can't find that they ever ran in a Formula 1 race.
This is not the exact car (I don't believe) but I think this car and engine are basically it sans supercharger:
Attachment 1089