Toilet Flange

My old toilet flange was a lead pipe with a metal ring slipped over it and the lead pipe edge bent over it. Because I've removed the old tile and mortar bed I cut the lead pipe a replaced the flange ring with a plastic one that has a bit of a tapered cone shape in the middle. Is this okay or do I need a perfect seal between the flange and the inside wall on the lead pipe?

BTW - I don't have access under the lead pipe.

Were you able to flare the lead out over the flange or is is just sitting there? A picture would help. Often, when replacing a mud bed with ply and cement board, the floor ends up being thinner. If there was enough lead, the better thing would have been to use another brass ring and flare the lead out over it. Not sure without seeing some pictures, and then, probably best for one of the pros to resolve it for you as to what your options are.

At first I tried to gently bend the lead back so that is was straight and I could remove the flange ring and get the sub floor down in one piece but the lead pipe was cracking so I cut flush with the floor. The new plastic flange is sitting inside the lead pipe. I'm guessing that the ID of the lead pipe is bigger then the OD of the plastic flange by about 3/8".