Single stage blowers are common. Dual stage not so much and from what I hear they seem to be too heavy for our little garden tractors.
That sounds better, I just opened the link and read the specs.
There seem to be lots of old Bolens blowers around, at least here. Is it worth it to convert one?
And from answers here, it seems they are available in drives in both directions.
These bercomacs have a great reputation and it's still heavy but I was able to pick it up off the back of my pickup by myself.