FLYBOYJ
"THE GREAT GAZOO"
I would say the relic lines up pretty good with the photo of the silver K5Y1 that Shinpachi posted.
On both there is a 'line' through the middle with 'stitching' lines on either side.
That line in the middle seems to be a dopped lap joint which is used to join "pannels" of fabric together. After looking at the info that Shinpachi has supplied, it may have been from the fuselage as it seems this aircraft makes little use of stringers. I'd still like to see any pics showing the stiching from the inside of a K5Y, but it seems that would be as rare as snake sweat!