interesting - I missed the reference to the US patent number - these are NOT easy to research - Yikes !!
Okay - possibilty here: the "whiteware" was produced by Hutsch----etc. It was exported to the US for the design application - are there any indications that the design was handpainted? Applied designs "baked on" ie: transfer designs up close always have the look of "pixels". Hand painted has brush strokes, no matter how fine. Some porcelain has a combo of transferware with hand done details -
Good pics - and with a handdrawn backstamp you might be able to have replacements.com do a search for you - see site for instruction
Re: the backstamp: there's a great Germany site called:
www.porcelainmarksa ndmore.com It's privately maintained by the well-credentialed Chris Simon Marshall. No values here, but lots of backstamps wth dates. Best wishes, KB