I'm not sure if I believe the DeRosa on Ebay is a 1974 model based on the top tube braze-ons, the curved wheel quick release and the saddle. My guess would be a late 70's or an early 80's model, ....unless it was repainted and the top tube guides added.
The pump script is early "De Rosa" but the decals don't seem to be.
DeRosa was using 3TTT in the 70's too, not cinelli, and the chrome fork seems to make the frame a later model too. But I'm just making an assumption off the pics in Ebay.
Brian Van Baush
Anacortes, WA USA