anyone know how much it will usually cost ?

 

It depends on the damage to the engine (and the rebuilder). If only the seals were damaged, it could be anywhere from $1500-2500. If other parts of the engine are damaged, the price can/will go up.

If you aren't doing to do any porting, you can buy a reman from Mazda for around $2000 (with your core sent back to them).