The Maine location is right. While several builders of WWII-era US Navy vessels were located in Camden, New Jersey, the specific yard of Camden Shipbuilding was in Camden, Maine.

It is confirmed by the US Navy in their Dictionary of American Naval Fighting Ships (DANFS):

https://www.history.navy.mil/research/histories/ship-histories/danfs/j/justice.html

Nice shot, Tony got it spot on she was built in USA New Jersey at Camden ship yard, 850tons, 165ft long,powered by a single triple expansion steam reciprocating engine, speed of 12 knots.
If any one wants to know more about these forgotten men and vessels I have just finished an excellent book by Ian Dear titled the The Tattie Lads all about RTS in two world wars.

SAINT CHRISTOPHER was not built in New Jersey but at Camden, Knox County, Maine by Camden Shipbuilding & Marine Railway Co. Laid down for the US Navy as rescue tug ATR-20. Completed April 24,1944 as HMS JUSTICE for the Royal Navy (Lend-Lease Act). Rgds

Great shot of this ex Rescue Tug. Built 1943 in New Jersey USA. Served in the Royal Navy as HMS Justice.