I would say you got a market buy. I show the coin sells for $88. Its a great coin for your collection. Its a beautiful coin and you didn't pay too much !
Coin Values list the coin at $125...You know you are getting a MS66. It is a beautiful coin...it is certified by a very reputable service...it is in fact real...the question is are YOU happy?? I have paid probably too much for coins because I was taken with their beauty and the mind-set that "I HAD TO HAVE IT". But I also picked up coins that I felt were deals as well (looking at Grey Sheets, pricing, etc.). Either way, I was happy to fill a "slot" and knowing that I had a given coin made it worthwhile.
I would say that IF you are happy with your purchase, and the coin "fits" with the rest of your Buffalo nickels, then you made a good buy. I prefer my Buffalo's just a little more honey colored, but other than that, I like the looks of your coin. By the way, what is a guy known as SilverDollarMan doing , buying nickels?