usnps uniform

All,
I would like to recreate this uniform. I aquired a 1930s USNPS hat and need to continue from there. I cant really find anywhere to purchase these types of things other than just waiting for them to come up on Ebay etc.. At first I didnt know what to search for.
It appears the pants are called riding breeches or in some cases johdpurs. The coat does not seem to have a specific name. I also dont know anything about the gaiters and how to tell which ones to get. I am researching on my own and making some progress. I want it to be as authentic as possible.

I guess I dont have a real question but I am seeking input and opinions and potential sources of correct bits.

The jacket looks like a WW1 doughboy tunic.

I too have always been interested in early 20th century uniforms, especially pre-WW2. The nps uniform is easily replicated consisting of: Campaign hat, green longsleeve shirt, black tie, post-WW1/pre-WW2 Army breeches, brown leather puttees/green wool wrap puttees with brown ankle boots, knee high lace boots. All of these items can be purchased in etsy or ebay over a period of time and can be easily pulled together with a bit of hunting. The only difficult items would be getting hold of a green 3 or 4 button jacket matching breeches. The closest thing I can think of would be the US Army class A green jacket but the breeches would then have to be the same color and material to match. Hope this helps.

The company What Price Glory sells reproductions of the ww1 tunics and trousers.

Yeah the tunic looks like a M1912 dress tunic. The hats were m1911 campaign hats. Leggings on the gentleman on the right look like M1910 leggings.