I mean, the point of the DNC leaks is that they (the party) helped a specific candidate (Hillary) - even before she was elected a nominee - so they in essence acted undemocratically.
Unless you're speculating that the GOP was secretly sheming for Trump - something which I find extremely unlikely - then it's more than possible that any GOP leaks would in fact help Trump, as well!
They'd be more than happy to release any information on Trump. Unfortunately, they don't hack the information themselves. Someone else has to send it to them.
Here is what Assange had to say about Trump: "I mean, it’s from a point of view of an investigative journalist organization like WikiLeaks, the problem with the Trump campaign is it’s actually hard for us to publish much more controversial material than what comes out of Donald Trump’s mouth every second day". Source: http://blogs.wsj.com/washwire/2016/08/26/assange-trumps-ever...