Thank you very much for this very informative answer.
For the dimensions :
First Sewar, length of blade : 21cm
Second Sewar, length of blade : 16cm
Third Sewar, length of blade : 21,5cm
Yes a silver part is missing on the top of the handle.
For the yellow color, I don't know if it's the brass under a silver plating? or if it's the remains of an old gilding ?
For the first Sewar, on the engraved part of the blade, there are few remains of gold.