I used cut down VBC D06 pins that I had laying around, I just cut them the same length as the TC4 ones. I used Tamiya pivot balls (cause I had them). The old style TC4 suspension blocks (the shorter ones) hold the Tamiya balls really well. I have since drilled a set of TC4 ones to 3mm. (Don't ask how I paid a machinist friend in beer to do it). Really it doesn't change the car much, the TC4 and TC7 are really close on geometry. It just makes it easier to install DCJ's. If I could have got a set of the Losi ones I would have just done that.
It is fun taking it to the track and having guys having to ask what it is....LOL