Its great to see people still love and using stoves made by me so long ago, I will answer a few things in this forum as i see them. I am Doug Crane Jr. my father was the designer, manufacturer and owner of Crane Stoves and sadly passed away about 10 years ago and ive been lost ever since as he was everything to us.
The model 44 firebrick can be made out of any refractory cement (its purchased in powder form usually and you simply add water.
Most people make the mistake of adding to much water, you want to keep it think for molding purposes and less sagging. You should chip out the old cement with a heavy hammer and long crow bar that is heavy (not a fun job, but its got to be done!), I will post a picture of the molds used to make that firebrick below for you, note: this can be made of any material such as flexable plastic or w/e you wish but what is important is the inside curve radius of the stove which you will be able to get after you brake out the old firebrick by using a piece of cardboard and making a pattern. one these steel molds you can see the slices to insert some wooden shingles which make removal of the firebrick after curing much easier.
the reason the firebrick was made in 3 sections was for one purpose and one purpose alone (to enable a one piece totally solid welded smaller stove which could pack a punch and remain airtight forever...) You could throw this little coal burner off a building and it will still function and remain airtight.
One person commented that the legs were at some point cut off his model 44 (i can only imagine this was done by someone to stupidly attempt in installation in a limited vertical space), THIS SHOULD NEVER BE DONE! those legs are critically important for the safe operation of the unit and we spent months going through UL testing lab's to perfect them to obtain UL approval's. I will explain what you can do to repair this yourself or better yet have some legs re welding onto the bottom plate (the legs should be made of simple "bar stock steel" approx 4 inches long (they CAN be strait 1/2 inch bar stock, each cut to 4 inch length if you wish), the original legs had bent angles on each end to provide more welding surface. You should NOT use any kind of "hollow" steel tubing for legs (this is shown to add to much heat transferring through the "hollow areas" on the leg and would not meet UL approvals for safety.
I do not mind at all people asking questions or wanting help in maintaining their own stoves.
Crane Model 44 Firebrick Mold