Jim I think the best I could do is rule out a few possibilities. From the photos it looks to me to be solid green on both sides with leaflets spread about 180 degrees around the petiole. I’d expect species with abaxial surface completely covered in lepidia to start showing at least a little bit at that size, which would rule out P arecina, hardyi, martii (and the old gaudichaudi), minor, perlmanii, flynii, viscosa and maybe a couple of others I’m forgetting. The leaf shape I think already rules out maideniana. I think the blade is already showing it will be significantly undulate rather than mostly flat so I’d say beccariana and lanigera are unlikely (although this is where I’d stop at ruling them out completely). Also the fact it’s still alive probably rules out non Hawaiian species!
Not sure that helps much - there’s still about half of the species I can’t rule out. For what it’s worth, P hillebrandii that I’ve grown and seen at that size are similar to yours, whereas P martii, napaliensis, minor and maideniana were already visibly different (although that could be partially due to growing conditions). P napaliensis tends to have smaller fronds relative to trunk size at that size based on mine and others I’ve seen but again I couldn’t conclusively rule it out.