Welcome aboard from ol' Wyo.
You have a terrific model. Before S&W assigned model numbers in
June 1957 the model was called the Bodyguard, named by a police
chief in Wisconsin in October 1955 when S&W debuted the model
at the annual International Association of Chiefs of Police
conference in Philadelphia, Pennsylvania. The original Bodyguard
was built on an aluminum alloy frame and was known as the
Airweight. It became the ".38 Bodyguard Airweight Model 38" in
1957. S&W introduced the carbon steel .38 Bodyguard Model 49
in 1959.
The roving J series serial numbers--the J plus two to five digits--
began in 1970 at serial number 1J1. Number 1J9999 preceded 2J1,
9J9999 preceded 10J1, 99J999 preceded 100J1, and so on to
serial number 999J99 in 1973. S&W used the series for Chiefs
Specials and Bodyguards. The serial number equipment S&W
used at the time could only stamp six characters on a J-frame's
small butt. By the time the roving J series was finished the
company had obtained new equipment capable of stamping seven
characters on a J-frame.
Obviously there were only 99 made for each three-digit prefix
so the numbers ran through quickly after 100J1.
Here are two ship dates from the database that bracket yours
and offer a relatively good idea when S&W shipped yours.
905J79 shipped in May 1973 and 911J52 in July 1973.
We do not know assembly dates, only ship dates, and S&W
neither assembled nor shipped guns in serial order.
The stocks on your Bodyguard are not original. They might be
what collectors call "semi-high horn" if they originally shipped
on a Bodyguard around March 1962 (first photo). They could
also be the standard magna stocks of that era, which came on
Chiefs Specials (second photo). They will have a large diamond
around the nut and screw escutcheons.
In 1969 S&W did away with the semi-high horn stocks and used
the standard Chiefs Special stocks on Bodyguards thereafter.
We like photos!