Man, if you are truly looking to get started at the club level, and if you have a $300 budget, try below:
I'd prefer the b4.2 factory team over the rb6 if you are staying rear motor - parts are so muck more obtainable at the store level.
Try this set-up - $300.
Grab a b4.2 factory roller off a user here - you can get one for about $120
From there, get below:
1.) Hobbywing Justock ESC - $41 (Do yourself a favor and get the LCD Program box for $20 as well).
2.) Turnigy Nano-Tech or Nano Tech Ultimate 4200/4600 shorty packs. The Nano Techs have a 4mm bullet connector, and the Ultimates have a 5mm, so whatever your preference is there. $37
3.) Trackstar 17.5T Motor - $38
4.) Trackstar 915 Servo ($37) or Turnigy 1258TG ($33)
5.) Get a new set of AKA Chainlinks in SS or Clay for $40 new
Total spending would be $300, and that is assuming you have a radio/receiver and charger already.
Again, just advice, but would get you a nice start, and you'll have better racing upgrades over an RTR.