Here are some other Navy badges.
Other Navy Badges
page 2
海軍徽章
Military Merit badge. Established 1935.
Marked on the reverse: 'Ministry of the Navy, pure silver.'
This is what has been identified as an IJN Aviation Pilot badge, documented to have
been awarded in 1944 to bombers who rammed their planes into the enemy.

See the discussion on
this military forum.

If you compare the pictures on the forum with this badge, you can see 2 differences.
One is the lack of an inscription on the reverse, and another is the pin assembly.
Since so little has been documented about this badge, it is hard to say anything
definitive about these differences.
2 documents awarded to the same sailor. The first is a graduation document from the Imperial Navy
Torpedo Academy, dated Meiji 44 1911 November 29. The actual name of the academy is not
torpedo but suirai, which refers to a variety of naval weapons including naval mines, depth charges,
and torpedoes.

The second one is dated Taisho 7 1918 May 1 and shows that Yokota Kenjiro was promoted to the
rank of Navy Petty Officer Second Class. His rank on the academy document is Sailor First Class.
Lapel pin from the Unabara-kai. Marked sterling silver with gold plating.

The Unabara-kai  was established in 1922 as an alumni association for the various
Imperial Navy Cadet Academies, the first of which was established in 1891.
Currently the group is concerned with veterans and supports various events, such
as golfing, concerts, etc.

This is a post-war badge. Their online site is
HERE.

Inscribed  'Unabara-kai Foundation.'
A rare Naval Academy badge.
OBVERSE 'Noble Warrior.' Laurel branches & anchor with chain.
REVERSE: 'Navy Accounting Academy.'

This Academy, called
Kaigun Keiri Gakkou in Japanese, was established in 1874 and abolished in 1945. However, it was called by another
name (
Shuukei Gakkou) until 1907. It was one of the 3 main academies of the IJN. The other two were the IJN Academy and the IJN Technical
Academy.

The Accounting Academy prepared cadets for accounting, budgeting, and supply center work.

The main campus was in Tokyo, Chuo Ward, Tsukiji, but from 1944 to 1945 four smaller campuses were opened because of the firebombing.
A Pacific War era Navy badge, perhaps aluminum.

Inscribed '[Imperial Year] 2602,' which is 1942.
Memorial stone for the IJN Accounting
Academy. This stone is in Tsukiji, Tokyo.
I believe this is a Special Naval Landing Forces (SNLF) patch.
I believe this is a Special Naval Landing Forces (SNLF) patch.
A rare Navy badge from the Usa Navy Pilot Regiment. Usa is a town in Oita Prefecture, and this base was established on
October 1 1939 under the direction of the Kure Naval  District.

Two aircraft carriers that were involved in the Pearl Harbor attack (the
Soryu and the Hiryu) arrived at Usa after the attacks, on
December 28, before departing for another battle.

What makes this base even more special is that kamikaze pilots trained here, starting on February 16, 1945. The units were
nicknamed the Yahata Imperial Protection Units. (八幡

The Usa Naval Pilot Base was disbanded on May 5, 1945. It had been bombed relentlessly (along with the civilians nearby)
and over 300 people died. The airfield was destroyed.
Very rare Imperial Navy Ministry Military Affairs Merit Badge.
Established in Showa 10 [1935]. It was usually awarded to people
outside of the Navy who made inventions for the Navy or any
naval-related technological advances. This award was usually
accompanied by a gold or silver sake cup.

Sterling silver.
'Imperial Year 2600 [1940]. Special Naval
Fleet Procession in Front of His Majesty the
Emperor. Participation Commemorative.
Held at the sea near Yokohama. Showa 15
[1940] October.'
Battle of Tsushima 25th Anniversary Commemorative Medal.
Dated Showa 5 [1930] on obverse. The design has the Navy
anchor and in the center is Admiral Togo's famous Z flag.
Surrounding this central figure are laurel branches, a symbol of
victory. The attached suspension device is in the shape of
airplane propellers.
'Award. Imperial Navy Commemorative Day
Athletic Tournament. Showa 3 [1928]