Thats about what my Dad's was that I got him. Ive got a small one that is about 200lbs and I got it through my sunken living room and in my office using a regular dolly and 1 other person.Yeah, pretty light. my cheap one was 500lbs.
I agree, just take your time and it'll go smoothly. I'd not stress it that much at all.
Are they interior stairs or external stairs that you're going to use?