Help me heal my brick....

This brick (photos below) is from a Serbian-made woodstove imported into the US.  When whole, the brick is about 14 inches long.  Because of the narrow dimensions of the brick, I'm not sure if there is a cement or glue that can fuse the two pieces together to be a strong as new??.......  A local woodstove supplier did not have brick of that length to cut down, so would need to custom order which might be pretty expensive.  I've reached out to the US importer to see of they have a stash of bricks for these stoves, but have not heard back from them yet.  Opinons as to whether this could be repaired?.....and if so, what kind of glue or cement to use for a good bond?  Thanks!

Many of the wood burners here in NZ have cast iron grates and back panels.

Without knowing the location of the brick in your firebox, would a cast iron piece fulfil the function of the brick if it can’t be repaired?

Gluing will rather not work. There is one compound for ceramists that fuses pieces together in kiln temperatures, but I never used it and you need a kiln.
Depending on the function of this brick and temperatures it sustains, you could drill it and tie it with high nickel alloy wire.
It can be easily cut from a large firebrick slab with a right equipment. I cut various bricks and stones to various shapes all the time and I have two 18x18x2.5 slabs at hand and Imer saw that can handle 1 m long cuts. If you really want I could fabricate one for you and you would email me a shipping label.

Is that brick or soapstone? Hard to tell from the photos.