It looks like youtube now has 60fps streams for h264 (DASH) with the itags 298 (720p) and 299 (1080p).
The only problem is that SVPtube detects them as unknown format and, unlike the other DASH formats, doesn't add the audio stream as the dub in MPC, resulting in video-only playback.
A video which already has this streams: https://www.youtube.com/watch?v=kMgxQHPnQj8