For something this simple, it took me quite some time to find it... all you need to do is get the "preview" data from the search manager instead of the "result" data when working with a realtime search:
var search = splunkjs.mvc.Components.getInstance("search1"); // get the search manager
var myResults = search.data("preview"); // get the preview data from that search
After that, you can simply use myResults.on("data", ... as you would normally do.
I stumbled across this fact in this splunk blog post; I failed to find any official documentation for this. Maybe it would be a good idea to incorporate this somewhere, for example here or here.