I don't think I saved any of my old Enco catalogs, so I can't say what model you have.
I do recall, circa 1975, buying a new Chandler Duplex 1/2" B&F head. I was surprised to see it was made in Muncie, IN, just about 80 miles from me. I was also surprised to see how ugly the workmanship was and I returned it to the dealer. I bought a new Enco made in France (Gamet) 1/2" B&F head and was and am very pleased with it. A very few years after I bought mine, they started selling an updated model with travel stops, which mine does not have.
Much later, after the rise of eBay, I bought an Enco 3/4" B&F head and found, though it looked like a Gamet, it said made in India. Didn't look bad, though.
As to what to keep, I suppose they are both pretty old, so best to try them out and/or take them apart to assure they are OK before getting rid of one.
Larry