I don't have a 750 either but I do have a 950. Again, a big brother.
Jake is right. Parts are available with no problems. http://www.jdparts.com
will let you look at the all the parts diagrams and if you have an account, you can order an parts that you may need and either have them shipped to your dealer or to your home.
I have operated a 750 a number of years ago. It was just as tough as my 950 besides the obvious smaller stature and lower weight. The horsepower differences are not that large either.
I ran the 750 with a 4ft. brush hog with no problems at all. I feel pretty confident that it would run a 5ft. grooming mower, but definately a 4ft. grooming mower. Sorry, I can't comment on the snowblower though, I've never been around one.
If I didn't have the 950 and a 750 presented itself at a really good price, I would jump all over it. Power steering is not a necessity unless you are running a loader. With 4wd, it is unstoppable. The Yanmar diesel just sips the fuel as well.
Hope that helps a little. If you have any specific questions, please feel free to ask.