Welcome to OTT!
If the tractor runs and operates fine, then I think that is a great price. The implements alone are worth the asking price.
I wouldn't discount a single stage blower, because they can work well. The question will be if the tractor has enough power to throw heavy snow. You may have to work at it slower.
Kubota's are very tough tractors, and they are pretty simple. When you consider the price against a stamped metal rider from Lowe's or Home Depot, you are getting much more with the Kubota. And, it is much more fuel effecient. The considerations will be what shape is it actually in, how was it cared for in regards to servicing and where it was stored, how mechanically inclined you are (even if it is in great shape, it is a 30+ year old machine, and will need some TLC), and what your wife's operating skills are. It will be a manual transmission, 3 speeds with high and low. They aren't hard to operate, but there will be more to pay attention to than with a hydro. They are small and nimble. What type of mower does it come with? I assume a rear finish, which takes more attention than a belly mower. Unlike a rider, you will have a differential lock, plus the loaded tires will give you good traction.
I hope it works out for you- again, they are great tractors if they were cared for, and if it is in fair running shape, then you can always get your money back out of it.
The other thing to consider is that it might be a grey market tractor. B6000's were sold in both Japan and the USA. It would be good to know which one it is- do you have any photos of it?