I am looking for an insert for a heatform fireplace. House was built in 1987 and I have attached a pic of the fireplace I want to add an insert too. Any suggestions on what to buy or what will fit? Also what will I need to do to have an insert put in such as Hearth extension or flue/damper changes? The size of my fire box is 33” wide, 28” high, and 24” deep from the center of the front to the back wall. The width of the back of the firebox is 22". The walls slope in pretty good from front to back. Hearth size is 12". Thanks for ideas and or input! I am a newbie with this stuff so take it easy on me!