Chinese blue and white censor

[peterp]

I cannot exclude this at the moment, Stan. However, you have to admit that with export to Japan it is difficult to find a reign mark. Most reign marks like the Chenghua mark were added by the Japanese themselves. With most export porcelain to Japan there is either no mark or, with the early ones a mark that is used specifically for the Japanese market only, like the ones on page http://www.chinese-antique-porcelain.com/chinese-export-porcelain.html (in the middle of the page).
Please note that during much of the Kangxi dynasty the use of a reign mark was prohibited, and later in the Qing dynasty, the so-called Kangxi-revival period, mostly four character marks were used on export porcelain.
I do not think we get anywhere just guessing. Be patient, the opportunity to identify it will come earlier or later.