it should be possible to mount m39 lens and focus to infinity on canon. their flange distances are ALMOST identical, so, you should be able to find a "stepup" m39 to m42 thing like this and focus to the infinity and maybe even beyond..
https://www.ebay.com/itm/M39-to-M42-Screw-Lens-Mount-Adapter-Step-Up-Ring-For-Pentax-M39-M42-LB-/161809092915