I don't know what model# that unit is in the pic but I can look at pics of a 353 unit in parts tree and see it is not the same. That appears to be a snow thrower. It might possibly be a haban unit. The way the pulley is arranged it might work on the 1440. Better pics would help. Any pics of the front view by chance?
I just looked at the craigslist add and it appears to be a Haban snow thrower. It might possibly work on the 1440 being it was meant for wide frame tractors. I have never seen a single stage unit on a cyclops style tractor. Maybe someone else will chime in. Sam the man what do you think?