Thanks, Newfiegirl. With that information, I was able to find more:

Simani is a band from Newfoundland. It seems they don't have a web site of their own, but there is a page about them at UpAlong.org and an article in Wikipedia. Several of their songs (but not this one) are listed at GEST Songs of Newfoundland and Labrador.

DARLING SAY YOU'LL LOVE ME is on the CD version of their album "Music and Friends" but it wasn't on the earlier LP version of the same album (1987). Creator's credit is given to "Pat Casey/Simani."