Just looked at the clubs website, says it can run any motor you want in the open class. I know you just want to have some fun, but i would actually recommend a slower motor, say 10.5. This is still extremly quick, but may be more enjoyable than running a mod motor as itll be easier to control. In mod, if you dont have a great setup, tyres arennt prepared properly, youll just wheelspin down the straight! Also i would recommend going to a race night to see what the other guys run. Then if you do decide to race, youll already have suitable electrics. Remember, you can always change motor in the future! 10.5 is also gentler on the car, mod rips through belts, driveshafts, diff outputs and bearings. Also if you are just starting again, you may have the odd crash. At extreme mod speeds, this will be you done for the day, and will be an expensive repair!
I would also think about doing the 17.5 blinky class. This requires no setup with the esc so no worry about cooking your motor. You can get a cheaper esc then, and if yot interested i have a motor and pinions for sale. This is because id recommend racing instead of just practicing, 17.5 blinky is a fun class nit taken to seriously at club level. So theirs no pressure, and then you haveother guys to help with setup/drivewith.
Also with mod you need to make sure your car is all aligned on a setup station which if you dont have access to already will be another cost.
Servo wise, i run a ko propo one10 response. You dont really need a high torque servo, in tc its all about speed (still need some strength in it though)