I'm also a little confused as the title of the thread indicates Aramith Super Pros, yet the photo you posted clearly shows an Aramith Tournament Set 7B and 5B. Were these balls advertised as Super Pros? Where did you purchase them?
That range is 14 grams. If you look at the data for real sets in the thread below, you will see that the typical variation within a set is about +- 1 gram. No manufacturer would be able to sell a set that used the whole tolerance range.
5.5 ounces = 155.9 grams
6.0 ounces = 170.1 grams
If you want to compare sizes, it is much better to measure the ball diameter. The spec is 2.250 +- 0.005 inches. Typically, balls in use will be smaller because they get worn down.
Here is the Aramith design that matches your title:
I was bored today so I weighed some of the ball sets I have for comparison purposes. About the sets at time of weight:
Aramith Tournament Set: Brand new, used a few times
Brunswick Centennial Set 1: Brand new, used a few times
Brunswick Centennial Set 2: Older, well used
Brunswick Centennial Set 3: Older, well used
Hyatt Bicentennial Set: Very Nice Condition, wouldn't be surprised if they were never played with
Dynashperes Bronze Set: Brand new
Dynashperes Platinume Set: Used condition, no blemishes
Dynaspheres Rhodium Set: Brand New
Original Cyclops Set: Used condition, no blemishes...
