Those Nikes are beauties. It's my understanding the first two digits of the style number are the year of manufacture, so my opinion would be 1978 as well. I'm not really qualified to say what they're worth exactly, but I imagine you'll do well with those.
I'd probably just auction them and most likely some vintage Nike collectors will get in a bidding war. I'd make sure to offer international shipping as well, if you don't normally. Lots of collectors in Europe, Asia, etc.
For goodness sake, it you offer international shipping on those, DO NOT utilize First Class International and make sure to properly insure them.