https://www.realorrepro.com/article/New-Porcelain-Marked-Nippon

The word below the maple leaf should be Nippon !! Nippon was only used between 1891 and 1921 !! After that it would say Japan !!
This is interesting reading on the Nippon marks !! When you get to the bottom it tells you what the mark should be !! I think yours are the original !!
The quality is correct for Nippon Porcelain and does show some age on the bottom !! However there are fakes and you need to know how to tell the originals from the repro`s !!