Sorry, I forgot to come back and update this thread after resolving the issue. The seller finally come through in allowing me to exchange it.
After much research, I feel that the lantaka shown here fell in the grey area of likely a money item and not meant for firing. However, typically the basic and early designs with open yoke are accepted as working pieces while the later more extravagant pieces were thought of as wealth items. I believe there also continued to be more basic designs produced as wealth items even after the accepted changes had taken place. This piece did test out to be made of all bronze except for the correct chaplets in place inside the bronze.
The most troubling part of this piece for me was the added material capping the end of the muzzle. Through research, I found a large percentage of "correct and antique" lantakas had the same feature. I am guessing during the construction process, there was reason for more material to be added at the end for some reason. Im not sure why, but it was definitely common. This can clearly be seen in this thread on the last picture at the bottom right-
http://www.vikingsword.com/vb/showthread.php?t=4249. It can also clearly be seen in this example with good provenance.
http://jamesdjulia.com/item/lot-1542...w-shinn-47729/
Finally, the casting lines would suggest it was made post 1800 with a two piece cast rather than the original method of a one piece cast.
Hopefully this will help someone at some point in the future.
Thanks,
Casey