Last I saw Roach was the christmas event on saturday, also if those are the old shock models from V2 I can provide you with better ones or would you prefer more accurate?
As for shock shafts the reason why there are only a few is because angles shocks provided to be a bit more tricky to line up as the old method was making the shock bodies and shock shafts as separate meshes, this was okay for trucks that had straight up and down mounted shocks. As for why they are on trucks that have a coilover/standard shock setup is because the shocks are a separate mesh from the chassis and through some witchcraft with the node/beam editor this makes it easier to have the shafts line up into the shock bodies and not have them poke through when compressed. We (V4 contributors) decided to leave a few trucks with shock shafts to give a small taste of whats in (kind of like the sponsor plates).
its just a matter of redoing all of the V4 trucks in this manner now.