I wondered–“a Russian whistle” ?
No bloody Zaporozhian nor Zahidnik way – them Catsap don’t play winds 
Svirél’, sopílka, dudá (etc.) slightly different things, with no clear-cut definitions (depending on the geogr. area) and thusly widely confused.
All, anyway, vertical flutes from Ukraine which is acknowledged by the author you link to–not Russia.
He seems to depart from the original designs by the extra holes to make it chromatic. The old folk instruments are diatonic, and many I think are not even Major tuned. It’s often like roughly equal holes about equally spaced, like on quenas, NA flutes, etc.
From the pictures, those the artist made are of the type with a full duct windway and a window. There are others much akin to the Andean Quenas (just a blade cut at the top, and you got to use your chin, else upper lip, as a “plug”). Others yet have a separate window, but you still got to “focus” the sound with your lips.
Basically, the svirél’ you spotted is quite modern (and little authentic), built as a whistle, except the window is turned down (great to evacuate the juice, esp. if you chew tabakey in concert…).
Detail pictures of the blade show he followed the standard recorder (and many wood whistles) window design.
Also, and that is “trad” awright, there is no mouthpiece “duckbill”: it’s flat, so you press your lips against the top, not around. The “new design”, har-har, of Calmont low whistles often advertised on eBay UK seems quite much the same.
Make it alto or tenor, and you’ll get a… zubívka. 
For more info, see this excellent page :
http://home.att.net/~bandura.ca/VMfolkBook/index.html
PS: You might make sure your Russian neighbour is Russian, or Bielorussian, or Ukrainian, or whatever else. Just in case you’d have to build a balalaika 
Btw, what’s his last name? Ethnic roots often coded there…