Are you sure they're "non-pop-up". In my experience, sprinkler heads that remain above ground have a very short life span.
I've always replaced any Toro sprinkler heads with Rainbird. Maxi-Paws for large areas and Misters for smaller areas. I especially dislike gear-driven heads (of all brands). I think that's what you have, but I'm not sure. The gear-driven are a pain to adjust and don't cover as well as the Maxi's.
BTW, the Rainbird Maxi-Paws are also designed to connect to 1/2" or 3/4". In addition, they make a spin-out wrench that lets you change the guts of the head without having to do any digging.