WW2 1219C2/USN MK2 knives had both unbent and bent guards straight from the factory. Many factory unbent guards were bent in the field.
The "modern offical " ones (20227) are all straight guards. Modern official ones are from 1962 onward. These were made by Utica, Connetta, Camillus, MSI and Ontario. Ontario is the only company still making 20227s under contract for the government. The 498 is the Ontario civilian version of the 20227, made to the same specs as the 20227. If you hold a 20227 and a 498 side by side, 99% of people could not tell which is which.
The modern ones all have straight guards, thin (1/4") pommels that are pinned all the way through.
When Kabar started making the 1217s (remakes) they deliberately made multiple detail changes to prevent folks from trying to fake them into WW2 originals.
First, they used the original thick (3/8") pommels BUT they pinned then rather than peening them tight. No WW2 thick pommel knives were ever made with a pinned pommel.
Second, the pins are "blind pinned", meaning the pins only go 3/4 of the way through the pommel and can only be seen on one side.
Third, the ricasso stamping font on the new ones are larger and deeper with wide font strokes. WW2 versions had a smaller font with thin, shallowly stamped strokes.
Fourth, the modern Kabar sheath has the EGA stamp. No original sheaths had an EGA stamp.
Fifth, the early Kabar remakes had a grind that stopped about 5/32" short of the bottom edge of the fuller, where the WW2 specs had the grind coming all the way up to the bottom edge of the fuller. Sometime around 2014 or 2015, the grind was changed to all the way up to the fuller to be closer to the WW2 specs. All other anti-fakery characteristics remain in effect.