You have a good QUIET cast iron system why ruin it with plastic garbage?
All you have to do is get a fire extinguisher and melt the lead type “D” off the brass ferrule that is caulked into the bell of this cast iron hub. Then get No Hub Cast Iron coupling and a short piece of NH pipe and a “Quick SET” no hub Cast Iron floor flange.
This is the BEST and easiest way to do it. Ta Dum
SylvanLMP