I tore out my old tile floor down to the sub-floor and installed cement board and new tile, now my cast iron toilet flange is one inch higher than the floor. The cast flange connects into PVC about six inches down. Can I cut the flange off at floor level and replace it with another one?

Do I need any special tools to cut the old one off?

I found a cast iron flange at the local home improvement store that has about a one inch piece on it with a tappered rubber seal that claims to fit into the existing pipe, do you think this will work?

I appreciate any advise that can be provided.