Fukagawa porcelain cup

This Fukagawa cup is about 2" high x 3" widest diameter. Hand painted, it has the Fukagawa mountain and stream mark on the bottom. Fukagawa porcelain is typically very fine, but this cup has many flaws. There are several bits (bubbles?) of debris in the glaze. There are also a couple of rough spots in the porcelain, pre-firing, and a bit of muddiness in the decoration in spots. It lacks the 3-d effect often seen in Fukagawa pottery decoration

I found this at a thrift shop after going to several shops and finding nothing at all worth adding to my pile. This little cup was a surprise find for $.99, all on its own. Perhaps once part of a set?