Thank you for the comments, everyone! I just assumed that the new UTI-4 t15B (kit no. 72315) was the same as the old UTI-4 from 15 years ago (kit no. 7231), with the addition of the sprue which includes the RS-82 rockets from the type 6 kit (no.72164), but apparently I was wrong. For those of us who don't own the new UTI (yet), HobbyTerra has sprue images which do show this to be a new kit:http://hobbyterra.com/product/polikarpov-uti-4-t15b-fighter-amodel-72315.html
As AaCee has already mentioned, this looks like it has some conversion possibilities; now I might have to buy a couple of them! Too bad Amodel's prices seem to have gone up so much...
Hi Massimo - the one-piece prop and spinner in the original kit (no. 7207) has a very flat spinner compared to the drawings in Maslov's I-16 book, so I replaced it. Another solution would be to build up the Amodel spinner, of course. Send me a personal message if you want me to do a canopy for you!