The Tekin seems to work a bit better than the SPX with slow motors + it can be updated anytime. So it is your best choice, IMO ( I do not own any of these , I just recently gathered some info in order to buy a new ESC. You guessed my choice...
For cheap the Yeah racing batteries seem hard to beat and perform very very decently, I'm told.
Servo : break you wallet, it is really worth it. KO 2413, Futaba 9551 or 9550.
17.5 or 13.5 rubber is indeed perfect for you. Just buy the Tekin combo with speedo, hotwire and motor.
Charger : I don't know. Seriously, the small Orion charger or any of its 474 clones will be more than sufficient.
I would not try to put anything faster than a 10.5 in a stock cyclone S. But with a few upgrades to the drivetrain ( diff outdrives maybe?) it should accept some wild motors.