looking for front upper Turnbuckles 3.5x24mm

[GO-RIDE.com]

The front upper arm turnbuckle is the weakest part on the crt.5, and the Ti ones are even weaker. If you can't get them locally, then try RCPlanet, Amainhobbies, Nitrohouse, or Impacktrc. They are all good, stock crt.5 parts and that part is only $4. I wouldn't bother with the hassles of ebay.

As for other parts if you drive hard:
Lower Arms
Upper Arm outer section
Steering Rack
Front Hubs & Knuckles

If you want to cut down on the upper turnbuckle from breaking then completely thread the turnbuckle into the upper arm parts and move the outer eyelet to the inner hole on the hub. You may have to back the turnbuckles out 1 turn to get the camber you want, but they will be a lot stronger.