Wow. NJ is a long way from Southern California. Styles are completely different. There are many outlets here that carry gas or propane fireplaces. In fact, we are considering one that was shockingly inexpensive ($2,000), but we found these cute little portable fire pits that use clean propane, so we have two of those on our property. No sparks or smoke ever. They are 50,000 BTU and put out a lot of heat. We still might get the fireplace for the highest point on our property. Other things have priority. Do a web search for BBQ/Smoker type stores close to you. They usually have pre-fab fireplaces too. Good luck to you.

(Even though this is a year late) I do not know what brand you have, but the clearances to combustible materials are going to be about the same for any of them. I do not know of any that would allow that base/enclosure to be framed out of wood. The dotted line represents the entire noncombustible zone. Your base/enclosure is just the smaller highlighted object in the middle. Make the structure out of brick or concrete block when you redo it.

Blowers are useless outside, since hot air just goes straight up. The only heat you are going to feel outside is radiant, and an unvented model is not the best choice for that. Both the Montigo and American Hearth/ White Mountain Hearth units are well made and will deliver drama. If heat is on your priority list, you might do a little more research and try to find a way to get some radiant heat. You might want to look into one of these: Town & Country WS54 Outdoor

I have the same issue, except mine had an electric heating element. I’m planning on doing a high-temp clear coat on the outside, high-temp black on the inside and base, then lining the bottom with firebricks. Fingers crossed!