Please Help Me Identify This Fireplace Insert

I picked up this fireplace insert on Craigslist, and it doesn't have any identifying marks. No name, no placard, no plate, no label. It might have had a paper one at some point, but it would have burned off.

Well made, decent design, just needs some new firebrick and some insulation on the doors to make it airtight.

This is the top. That's a US quarter for scale. (Didn't have a banana, my bad.)

It doesn't look like it was designed to have an adapter for an insulated chimney liner. It looks as though it was designed to just get shoved into the fireplace and run raw.

That's the flue plate.

The back. That's a panel for putting the air blower in the back, instead of the side.

Left side view. That's the vent for the air blower.

Right side view. That's another port for the air blower, and I think that's a port for a gas pipe, in case you want to add gas logs, or a gas log igniter.

The bottom.