In my opinion, you should try selling them on ebay or something simliar, to see if you can get a better return above face value, before simply putting them in the bank. There's bound to be someone to pay close to the catalogue price if your lucky, especially on sites like ebay.
Also, once again
in my opinion, because you have 3 consecutive it would be more valuable as a lot. This is because these notes date around really anywhere between the late 60's to late 70's...(the "lawson Bouey" signatures on the note makes it later in the series which started in 1954), and $3000 in the 70's was alot! Would have been about $15 000.
So if you think about it, how many people would have put away 15 000 in cash!
IMO it is rare to find three in series....on their own $1300 each...3 together i think you would be lucky to get $4000-$4500 to the right buyer, just for the sake of having 3 in sequential order...
However i have learned that only a few buyers/collectors care about sequential....i just think it would enhance the rarity to have the 3 in series, being such a high denomination...
Once again just an opinion! Maybe just putting them in the bank is better