Beware, this lock is either a copy of an authentic lock or an outright fake.
this brass lock was made in phila, pa by the w. bell and sons locksmith company for the USN - it is marked federal # 5 and 4 brass levers- it is 2 3/4 x 4 inches closed and comes with its original 2 keys-each key has the numeral 5 on them-this is an official us navy dept lock - eBay
My guess is that this lock was made in India, Pakistan or some other place in the region. Look at the key. When was the last time you saw an antique key that looked like that? Also, this lock has two keys which is a rare find for genuine antique locks. The lock looks brand new, which if it were real would of at least shown signs of longterm-storage or at leat minimal use. Also, if still 'new' where is the package or wrapping? Including that in the offer might result in a higher bid price. I had actually purchased the first one of these that I had seen listed but ended up returning it as it was obvious that it was a fake upon receipt. Which my lock mentioned that it was all brass, as this one proclaims, the internal pieces were not made of brass, and were already somewhat rusted.
There have been other variations of this lock to appear in eBay which at least makes it easier to spot them as fakes.
This item sold for $11.50 (Plus $6.45 in shipping.) It is OK to buy a fake, provided that you know it is, and I would also say that the poster admits as much. This listing proclaimed the item as genuine.