I have gotten tired of responding to questions about this series of spoons. Please folks, no more emails about these spoons. The set was made by International Silver, who owns Oneida, who owns Roger Bros. The spoons bear all of these various marks.
This series of President spoons are silver plated
They are VERY readily available individually and as a complete set
I am not sure as to when the set ended. I have seen Kennedy, and think that I have seen Nixon.
I do not have any interest in these spoons and to my knowledge there is not a lot of interest among serious spoon collectors
As for price: I have seen them priced anywhere from 25 cents to $3.00 each. I have seen the complete set priced from $50 to $150 (including rack). Packaged sets of 3 are also available.
The most valuable part of the set is the nice spoon rack which accompanies the complete set.
Unless you really like Presidents, I would suggest that you find some nice sterling spoons to collect. This museum is full of great possibilities.