Interesting thing is Britain and the anglo-sphere in general we don't have gendarmerie. In England we have nothing like it and no history of it. So I find it a strange concept and way of doing things personally. Though I do agree with you about how it would be preferable to army or just police.
The Crown Reserve Police became the Central Reserve Police, 300,000 strong today (benchmark figures 1.2 million for the Indian Army) organised in 200 battalions of about 900 constables each (135 per company, 7 companies =) 945 to be precise, each headed by a Commandant, that being approximately equivalent to an Army Major or a Lt. Colonel.
Then there's the very active Assam Rifles, deployed almost exclusively in the north-east of the country, about 65,000 constables, but entirely with officers seconded from the Indian Army.
The Eastern Frontier Rifles was the crack troop component in the east, but has become a sleepy, underemployed, 2 battalion force entirely manned by those Gorkhas who normally go into the 11 GR. The Assam Rifles also have very large numbers of Gorkhas, putting them third in line (leaving aside the Singapore and Brunei contingents for the moment) for Gorkhas who want a military career, after the British Gurkhas (around 4,000 and shrinking), the Indian Gorkhas (around 40,000, in seven GR regiments) and the Assam Rifles (65,000 men, but with strong elements that are not Gorkha).