Overall the engine is .... not very encouraging, but you got your money's worth with the burner alone, and I see several individual parts that look quite salvageable. On the other hand, there is nothing so bad that it can't be fixed, it is only a question of how far you are willing to go to fix it, what all can you actually source for it, will it be worth it, and how much of it will end up really being original.
Often in a case like this it is far easier to build a whole new engine from scratch!