You should be fine bringing one in. We took some in that were definitely non-Disney. Only issue I had was that I dropped the hilt at the Security checkpoint. Totally my fault. It still works though.
As for the sleeves, we don't use those. We made our own using leather, a pool noodle; and dice cups (for the ends). Much more durable, and we didn't worry about breaking the "blades". I've seen people bring theirs back into the parks because of issues with it, etc, so I don't think you'll have issues. Luckily, with the trams running again, it's a quick trip back to put it in your car if there is an issue. Some CMs can be overzealous at times.