"I own one such periwinkle that is pastel blue afterall."
Definitely one of the hazards of buying on eBay. There's almost no way to know the color for sure unless the photos are excellent.
In this case I noted the seller called the color "blue" and I was pretty sure then they were periwinkle. Just looking at the photos, I'd guessed either gray or periwinkle.
Of course the huge (and expensive) error the seller made was the misspellings. Snorkel hunters using eBay's search function were never going to find this set, and of course listing them in "Sets" meant a buyer would have to scroll through the category to find them. I was lucky that eBays algorithms showed me the set as a tease when I looked at a similar Sheaffer set.