Flange not entirely covering hole

My commode was leaking onto the floor so I removed it and uncovered a rusted metal flange not entirely covering a hole cut in a tile. What is the best option? Do I simply apply a new seal and re-bolt the commode to the floor? Do I need to somehow twist the flange to better cover the hole first? Or, do I mount a new flange on top of the old one? I attached a photograph so you can see what I described.

As long as there is a good seal, I don't see why it would matter if there is a little gap like that. And if there isn't a good seal, then water will leak even if the flange does cover the entire hole.

Come on guys! There's only one way to fix this right. Remove the old rust out flange completely and put in a new one. Sure, it might seal for awhile, but it's not going to be a permanent repair except by total replacement.

If the rust is superficial, then it will be okay. If it's rusted so bad that the bolts will pull out of the slots, then Gary has a good point.

I'd get the lead out of there! Have you got a basement below there?