I am not sure if this Rubb’r-Niks Figure is the first figural Aquaman toy, but it must be one the earlier ones. The Justice League Rubb’r-Niks were released by the Canadian company Multiple Toymakers back in 1967. Aquaman came as part of a 4 pack that included Wonder Woman, Batman and Superman. As you can see, realism was not really at the top of their list when trying to represent Aquaman. I actually find his white face a bit scary, but it is its odd coloration and simplicity that makes this figure (and the other Rubb’r-Niks) so charming.
If you ever get to see the whole Rubb’r-Nik set, you will notice that the Batman and Superman also have the painted face, but Wonder Woman does not. She does not stand out as much, but the representation looks a lot more natural. I wonder why they made that choice?