One of my local gun shops has both a S&W M1917 revolver ($650) and a Winchester M1917 rifle. ($995)

Not sure how many of the parts on the rifle are Winchester, but the stock is marked "American Legion Post 459" even though the rifle appears fully functional.  I though them and the VFW only got non-functional ones for ceremonial use.

And me without much in the way of free $$$. 

just did a quick google and found American Legion Post 459.  3 listed, Michigan, Ohio and New Jersey.   wonder which one it is.    As I recall, the Legion posts used to get rifles from CMP or the Dept. of the Army for ceremonial purposes.  I was under the impression most had been either deactivated or modified to accept blanks only for funeral service salutes.  I was also under the impression that legion posts were not allowed to sell them, but had to return them to the Dept of the Army when they were no longer required.    I could be wrong,  it's been known to happen. 
 It would be interesting to learn the story of that rifle.

 Ah...hmm...uhm...welllll...might depend on the post and when they got them...

I happen to know a "de-activated" German machine gun (not sure model) that was hanging in a local VFW post got "lost" when "people" found out it was....ah...not so much, to prevent it's total loss/cutup.     I can imagine that at one point there might have been unofficial/real rifles in use.

 As for price...I can't say on these guns I know much, depends on condition/matching parts.  This spring I bought a Remington 1917, all-matching, mint bore, worn outside for $450.