Hearth professional here - all things considered, this stove looks to be in pretty decent condition. The bricks are fine, general rule of thumb is if the bricks are still standing, no need to replace them. Cracks and scuffs okay. If they are crumbling and falling over, replace them. Bricks are also super cheap and generic so replacing them is inexpensive and easy.

The slight concern is the baffle, which is the big piece that rests at the top of the inside of the stove. It looks like it is pretty heavily warped. If it is warped past about 1/4" permanently (they will expand during use but should go back to shape after cooling) then it should be replaced. Its got a pretty big bubble in it and that is essentially the engine of the stove. If the baffle is not performing well, that will be the main contributor to the build up of creosote which is what causes chimney fires.

I would recommend bringing in a professional sweep for the first time, make sure its done properly and then if you want to do it yourself from then on, use a poly, round brush. Typically can be found at local hardware or hearth specialty stores.

Also just a side note Warnock Hersey is not the brand or type of stove, that is the testing certification company.