What I’ve seen a guy do before is he bought refractory mortar from Lowe’s (comes in a bucket) and lined the firepot with it. Let it dry and started with small fires and worked his way up to bigger fires to cure it.
My wife and I recently purchased a home in Woodburn Indiana which included a beautiful non-functioning stove made by “The Eclipse Stove Company” out of Mansfield, Ohio. The stove also has the wording “Century”, “No. 16”, and “Stoves and Ranges” impressed on it. I have a local sandblaster and jack of all trades waiting by to renovate it but first I must address the missing trim around the skirt and busted grate. Our hope is to get it functioning to help absorb some heating costs this winter or next. Any “Wisdom” you can provide is very much appreciated. If it proves too difficult to renovate we’ll probably put the funds toward a wood burning insert in the another fireplace in the house. First I’d like to renovate this beauty if at all possible.