not sure on the year but I have difficulty lathering today's formula whereas the older stuff works quite good. the older ones I have don't have a barcode on the box, if there's a price still on the box it's usually less than 40 cents, the first ingredient listed is tallow (not potassium stearate), and the city of manufacture is either in CT or NJ. however, I've got half a dozen pucks of the new stuff so your recipe intrigues me. Ps. if you've been wet shaving since the 70's, don't let anyone call you "vintage". what you are is "mid-century modern".