I'm in the middle of doing a bathroom remodel for a house I just purchased. I wasn't planning on doing much to the toilet, but during demo I discovered that about an inch around he flange was rotted and the toilet was rocking so up it came. I found that I had a brass flange (that was once, but not now) fixed to a lead closet bend. The lead looked like it was in pretty good shape. I'm sure it's original.
Most of the DWV in the house is cast iron with copper and PVC patched in here and there. I didn't know this was something special until I did a little research after the fact. I didn't open up the floor in this joist cavity, so I'm not sure how it connects to the stack.
Because I was raising the floor 3/4in, I needed to raise the toilet flange. I found a cast iron toilet flange at Lowes that had some sort of gasket around the bottom. I can't find the exact one online, but it's similiar to this one: http://www.*********.com/cmc_upload/...69355-wc_3.jpg
It fit right inside of the lead closet bend with a tight fit. This I could bolt down to the floor. Is this ok to continue to use, or should something else be done? There is about an inch or two of overlap where the cast iron is inside the lead. Doesn't leak.

Thanks,
Jason