The master tiered clubs like the R9 or Supertri, and the irons like the G10's and I15s all have fairly faster meters. What you can do is couple those with a GI ball, GI3 just came out and should offer you the slowest meter possible on those clubs. Depending on your goals with the game you you might be fine with your rapture irons and maybe just pick up a driver that will give you 25 extra yards off the tee. My suggestion is to pick up some GI3 balls, rent a master driver and use it for the day and see how you do. If you seem to handle the driver fine, then maybe buy it and add the irons later.
Best of luck, congrats on making master.