Stuby - since the DX3R does not take a module unfortunately can't be used with mini-Z's. Airtronicss M11s & Futaba 3PK's as far as i know set up as left handed and they do take the module via an adapter and some racers are still using them at highest levels of mini-z competition.
Not sure if any of the KO radios set up as left handed so please do a bit of research (I'm guessing they should be capable of being set up as left handed since they are competition level radios ) if they do, they are the best way to go & again look into used (Helios/Mars or other) and then just add a module.

Everyone who I know that has set up an RCP track at their house has absolutely had a blast running mini-z's