[skil55voy]

I would like to give a bit of a different perspective. When I was collecting as a kid, I started in 1962. I was able to complete that set as all of the Series released by Topps made it to my local stores. (St. Clair Shores, Michigan). I looked forward to the 63 set. However, I was only able to get cards into the 4th Series. No boxes for 5th, 6th 7th ever made it to the stores. In 1964 I made it to the 5th series. In 1965, I was able to complete the set as all Series showed up. 1966 all the way to the 7th Series. No 7th Series boxes showed up. 1967 I was able to get to the 7th. In 1968 and 1969 I was able to complete my sets.

When I started collecting again in the 80's the cards I found to be difficult were the 63 6th and 7th, 66 and 67 7th.

As an aside, I completed sets from 58 through 61 and did not have that much trouble. I was fairly close to completing the 56 and 57 sets but sold the collection before I finished. Also, in 66 you could write to Topps and get cards for 4 cents apiece. I picked 10 numbers from the 7th Series at random and sent away for them.
In 70 and 71 I ordered Series 5 through 7 for each set for $2.25 a Series.