Purchased directly from James Sego, which at the time was the #1 set of Eisenhower Dollars on all circulation strike sets.
The 1970-D Eisenhower Dollar is very common as they made them by the tens of millions. Only in grades of MS66 and MS67 does it become scarce. In MS66 there are probably about 1,000 to 2,500 examples that survive. In MS67 condition no more than a dozen are known to exist with no coins graded MS68 or higher.