Eugenia smithii. It has more recently been known as Acmena smithii for many years.
Recently the Australian Acmena species have been moved into Syzygum.
So this plant is now Syzygium smithii.
The only Australian Eugenia I can think of is Eugenia reinwardtiana, the Cedar Bay Cherry.
That plant is clearly not a Syzygium or Acmena.
Don't know how that would impact grafting compatibility, but the former E.smithii may not be too close to Eugenia species ??