There are a number of variations in the Type 99, mainly due to its undergoing modification and slmplification as the war went on and Japanese resources dwindled and the need became more acute. Unnecessary finishing steps, such as knurling of the safety, were skipped; a simple peep sight replaced the elaborate rear sight, a tacked-on wood buttplate replaced the steel one, chrome plating the bore was discontinued and so on. The very late rifles are rough, but for the most part are safe to shoot.
I know of no reproductions of any model of the Arisaka, but some Japanese pistols were copied as non-firing replicas; those should not be capable of firing and should never be modified to do so.
There are also Japanese training rifles, made for their equivalent of high school ROTC. They were made of cast iron to be used in firing blanks. None have the Imperial seal (chrysanthemum) or normal markings, and for the most part will not accept live ammunition. Those are actually dangerous if they will fire live ammunition.
Jim