[Would you like to see this in-game?]
TL;DR: A Type 63 with improved seaworthiness and a 105mm cannon.
In the late 1950s, China had gotten their hands on a few Soviet PT-76s. These vehicles were evaluated by the PLA and, in 1958, it was decided that a domestic copy was to be produced. The first design came to be known as the Type 60 and was tested in 1959. A number of issues were observed, leading to the PLA rejecting the prototype in its current form. The No. 60 Research Institute of Fifth Ministry of Machine Building and Military Engineering Institute were called in and tasked with refining the rejected design. This lead to another prototype being presented to the PLA in 1962, this time meeting expectations. The design was passed on to NORINCO and the Shaanxi Weiyang Diesel Engine Plant where it was modified once again and approved for production in 1963. This vehicle became known as the Type 63 and entered service with the Chinese military, however, while accepted into service, the vehicle was not without flaws. The 85mm cannon present on the Type 63 was fairly weak and, while amphibious like its PT-76 roots, its seaworthiness left a lot to be desired, especially when it came to cross-sea operations. Some time in the 1990s, work began on an upgrade to remedy these issues. The resulting vehicle was designated Type 63HG, also called the Type 63 Sea Reform. This upgrade essentially transformed the Type 63 into a ship. The hull was extended forward and took on a bow shape, allowing for a top speed of 30kph while in the water, and the 85mm cannon was swapped for a low-pressure version of the ZPL-83 105mm cannon, which required the turret roof to be raised. The Type 63HG was tested alongside the Type 63A but was ultimately not accepted into service, with the Type 63A being accepted in its place. It is unknown what happened to the Type 63HG prototype/s.
Place In War Thunder:
Amphibious capabilities have always been more of a gimmick than an actual advantage when it comes to War Thunder. This is largely due to maps not being designed with amphibians in mind, however, another factor that plays into it is how slow amphibious movements are. In a meta dominated by speedy movements, its no wonder why sluggish amphibious assaults aren’t considered viable. The Type 63HG, while not magically making all amphibious assaults viable, definitely makes them more viable. 30kph in water is very quick. As a result, you could appear in certain locations faster than anticipated, potentially taking a few enemies by surprise. Considering the Type 63HG’s prototype status, I think it would be best implemented as a rank V GE premium or battlepass vehicle.
Armament: Low-pressure ZPL-83 105mm cannon, 1x 7.92mm MG, and 1x 12.7mm HMG
Dimensions: 8.44m, 3.20m, 3.12m (Dimensions of the standard Type 63. This vehicle is a tad longer and taller.)
Armor: 14mm max
Ammunition: APFSDS, HEATFS, HESH
Speed: 60~kph (land) 30kph (water)
Being tested alongside the Type 63A:
PT-76 - Wikipedia
Type 63 (tank) - Wikipedia
Type 63 light amphibious tank - Chinese PLA (1963)