Not much hop up parts for the DT-02. Search for DT02 or DT-02 on eBay. A few items can be found/sourced there specially from seller jr-rc (Jason's store).
DT-02 and DF-03 chassis are too different, so most, if not all, DF-03 parts/hop ups won't fit.
If possible, you might opt to get the Dark Impact/Keen Hawk, if hopping up a kit is your thing.
Team Associated B4 * T4 * B44
Novak BL * Futaba TX/RX/Servos * Hyperion/Megapower Chargers
Orion/Yuntong/Maxamps Lipo * AMB #6655738