You have a tractor that is at the very bottom of the pto hp scale, and if it has been used, may not even be putting out the 12 full hp that is advertised.
The minimum pto hp for the blower you have, is roughly twice what you have, making it about 30 inches too big.
There is more involved than length.
Yes, you could possibly run a blower as big as 48" with that tractor.
But to work well, that would be a lightweight blower, that is especially made, and geared, for a low pto hp tractor.
And also, "running it" is subject to interpretation. What some consider as acceptable, others may not.
Personally, without a cab, I would not use a snow blower. It can be a lot less than fun, (especially rear mounted).
How about a nice plow?