France dwarfs Oceania: about 635,064 km² km² against 8,600,000 km² km². At true size France is about 13.5× larger — the whole of Oceania fits into France roughly 13 times.
The old Mercator map treated both about equally (1.9× vs 1× inflation), so at least their relative sizes were preserved — even if both were drawn at the wrong absolute scale.
France fits 13× into Oceania.