My vendor had a Magpul grip that had the trigger guard connected to it. That way you only need to do one roll pin. However I can't find any info on this grip. Everything now is the two parts separated.
The now-discontinued Magpul MIAD full grip kit contained a frontstrap with an integrated "enhanced" triggerguard. If you run a basic Google search for MIAD Full Grip Kit, you can still find them for sale.