No. It has not been flipped. Being young and ignorant of a lot of the terminology, I have to ask, what do you mean by the Braze-on's for a rod operated drum brake? Is that the little bit on the bottom of the bottom right rear fork?
Other features: It has an interesting two bolt clamp for the eccentric front bottom end. It has the number 141 brazed on between teh two bolts under the frame. In the crotch of the rear fork there is a large screw that I think was probably to hold a mudguard, but am not sure. Any other photos that might help identify it? The serial number is stamped in at the top of the rear seat post - s18969.
Thanks for the help,