Im sure it was produced by a Naples factory but it is not of the original capodimonte factory. A guess without seeing a clear photo of your mark I would say it was made by Marchese Ginori, After acquiring the Capo-di-Monte molds in 1821 the Marchese Ginori marked pieces with a seven point crown with N under. I would check Marchese Ginori marks as more than one was used & see if it matches and if it does you can get a time line of production.