No matter how much he can smooth a trigger, he can't turn a single stage into a 2-stage trigger. Unpossible.
I'd focus the money on the backup gun for the wife first, before the deployment, before spending it on the SSA-E. An alternative to both courses of action is picking up the Armalite 2-stage NM trigger. It's a damn good trigger, adjustable at the user level, priced great, and will work well for you. Upon return, spend some deployment cash on the SSA-E, and put the Armalite NM in another build.
I'm betting there will be another build... I'm just sayin'...