In the top picture of 4 guys.  The guy in the far right definitely looks like he's wearing a Philippine buckle.  The other 3 guys look like they have regular buckles. In the second picture. The Vietnam Vet on the left looks like he has a Zippo belt buckle on if I were to take a guess (looks like the ship's crest on the left side of the buckle and his ship on the right side).  Cool picture either way.  Looks a little like it might be in Hong Kong.

Regarding the date of brown or cordovan leather to black color change, here is what I got from Google. I believe the impetus was SECDEF McNamara.  He ordered the services to standardize uniforms and equipment as much as possible for cost efficiency:    "The USMC officially changed the leather and button color from brown to black in 1964. Before this update, uniform buttons and leather accessories were predominantly "cordovan brown" or bronze, but this transition to black helped standardize the uniform's appearance across the force."   Coincidently this is also about the time when the Marines gave up their distinct utility uniforms - as featured on the TV show Gomer Pyle - for the OG 107 sateen utilities used by the Army.

EARLY UNOFFICIAL MEDICAL SERVICE CORPS INSIGNIA   CHANGE to AR 600-35 dated 1 June 1948 created the new-collar insignia for the recently established MEDICAL SERVICE CORPS First example shown below is the ERROR Release. The official design has the MS on top of each other as shown in the second example shown     This is an early example of the UNAUTHORIZED Version, apparently a few were released before the OFFICIAL Design was created   UNOFFICIAL ERROR   Official Released Design

Got this crest at a show, described as US Military advisor,  I can use some more help.

Looks great!

I am on vacation and this is the only picture I have of my surplus corner. I can't get any more pictures of the gas masks till next month thank you guys though for helping!  

I got each gas mask for $5 at a reenactment, it's just a cool for display, I'm not wishing to preserve them, as they are already too far gone come up besides, the filters contain asbestos.  

Thank you guys! ❤️

After the Bell Crowns (or as my Dad called them, Pee Pots) until 1937 I believe, with the new uniform regulations. You will also notice the narrow chin strap from that period.  Here's one:  

Nice liberty pass.   I might have one or two from the Tulsa or the old Asiatic destroyer tender Black Hawk  (AD-9) circa 1929-1936 issued to the sailmaker's mate who owned the two Tulsa ships company photos.   Interesting trivia,  during WWI  Black Hawk was assigned as tender and flagship to the North Sea Mine Force and stood out of  Boston in June 1918 to take station at Inverness, Scotland. She remained there until the end of World War I and then shifted her base to Kirkwall, Orkney Islands, for the North Sea mine sweep.   My gramma's oldest brother was a mustang ensign on USS Saranac, one of 10 mine planters in Mine Squadron 1 (also known as the "Yankee Mining Squadron".)   Navy history is fun with all the connections like that.    Sometimes the puzzle is easy-   Lan O. McGriff (1908-1971),  I'd bet a lifer,  born in 'Bama but stayed in San Diego for the best weather on the planet and the sea, like so many Navy guys.      https://www.findagrave.com/memorial/211503595/lan-o-mcgriff   River Rat1,  hope you don't mind your original post about your b&$chin', engraved. sterling 1905 bosun's pipe taking a side tour, but I figure a 4th gen Navy man wouldn't mind.  I'll try to get back on course.  Here's another English made boatswain's pipe,  a poor cousin of yours, made of brass and with a 50" long brass lanyard, both with 120+ years of honest patina.    As mentioned, it was owned by a Rhode Island born,  USN lifer who enlisted in 1897, was shipwright on the USS Iowa during the Span Am war and rose through the ranks to Warrant Officer Chief Carpenter.    With the 4 foot lanyard, he might have used it as a measuring tape or a lead line.   The bowl isn't dented so he never tried to tune it.  He died of a sudden cardiac condition at 57 in his 36th year of service at NTC Newport Hospital in 1933 and was posthumously given rank of LT in the Construction Corps.   This pipe and his leather-bound CSC book came from his granddaughter, whose mother was the baby in this picture,  ca WW1.   I also have his rim impressed Sampson Medal, purchased out of Texas, where it had wandered over 75 plus years from Rhode Island, where his family lived and he's buried.