That said, if the marks you find after Googling date your pieces to the 20's--they're still worth a little bit. This mark was used on many different Noritake pottery pieces, not just the Blue Phoenix, that pattern mainly surfaced and was popular in the USA in the 1920's. I have some antique dishes, Flying Turkey, with the "M" mark in a wreath, "T" mark in a wreath or triangle, and "TT" in triangles. Though you're dating them early 19th C., Noritake used the M ( yep, an M, not an N) within wreath mark from around 1914 when they started to do a lot of exporting up to 1940.
June 22 at PM Preview: Noon Sale Day Antiques: Maple extension table with 5 leaves and 4 maple chairs (refinished); Victorian 3pc.
Prices people ask do not usually reflect what an item will actually sell for - but it is a good start.
China and dolls are very difficult to sell and a lot of trouble to ship (and insure) so I hope you plan to keep your china - use it - enjoy it.
On average, a vintage set for 12 of Japanese Meito China in their Ivory line sells for 0 - 0 on today's market.
Currently, the fine china for dining market is rather slumped and sets sell for considerably less than they did a few decades ago and moreso since the Recession.