Oh my goodness! I live about 25 minutes from, and used to work, in Williamsport. As soon as you described the shop (before I noticed where/who it was) I thought of a place I once visited when looking for a used sewing machine! Turns out when I read to the end of your post that I have been in there and you described it perfectly, except you left out dark and dusty...
I am so sorry you had this happen and so close to Christmas. I live 60 minutes from my Bernina dealer, but he is great and services all types of machines. He is located in Mifflinburg. There is also a place that handles a number of kinds of machines just about 5 minutes from the place you visited, on Basin St near Starbucks. I don't know them personally, but have been in the shop and they are pleasant and helpful. If you need anymore info, just PM me.
My DH says he goes in there every once in a while just because it is a verrrry interesting place...no one seems to care if you buy anything or not. (don't know why he would find it fun, but then... ) :shock: