Here's a MIDI file of "Happy Days Are Here Again", played by
Phil Lynch on Atlas piano roll no. 3975:

https://tinyurl.com/t8wmcvv8 "Happy Days Are Here Again"

This MIDI file was made from a video by Randolph Herr. The video was
recorded at only 30 frames per second and the video reader made the
tempo a bit uneven, certainly unsuitable for roll recutting purposes.

If anyone has an actual [optical] scan of this then I would appreciate
a copy. :)

Piotr Barcz