I couldn't find anything similar online but the mark is pretty convincing... Could it be of the period?
pesonally i don't think so. I believe it would be pretty rare, because as far as i know porcelain from that period and with marks are rare. And there are plenty of porcelain objects with qing dynasty marks under them that are not of the period as you might be aware of. but you could always wait for someone else to reply and see their judgement.
The mark looks as if it is not underglaze but was added on top of the glaze after firing. This is not a traditional way of production for blue marks. This is not that old, probably.