Tires: Alignment Shop Suggests Tire Replacement, alignment specialist, alignment shop

Question
My 2008 Hyundai Accent was pulling to the right, so I went to a well-respected alignment specialist who aligned the front end, then rotated the tires and found that it then pulled to the left.  They said the tires were the problem and should be replaced even though they should have another 20,000 miles left on them.  I called Discount Tires and they did not not have the tires in stock that were on the recommended list for the car.  They recommended I get 185/65/14 tires (in stock) instead of the 175/70/14 tires on the list saying they would give more stability on the freeway.
Two questions: 1.should I replace the tires and 2. should I get the different size?

Answer
Dora,

First a test.  Swap the front tires side to side:

If the pull changes direction, then the problem is 100% tires.  Replace them - and Discount Tire's suggest is a good one.

If the pull doesn't change at all, then the problem is 100% vehicle - very likely alignment.

If the pull disappears, or changes (other than a complete change in direction, the problem is both tires and alignment.