I saw that, but he asked about kits, not steel toys. The reason I suggested the two snap kits is that they (1) aren't terribly expensive like the Trumpeter, vintage AMT, or Revell of Germany fire apparatus kits, and, (2) they have fewer parts to break or break off.
He's actually better off going to a toy store or Wallymart and buying a heavy plastic fire truck, like the ever-popular Tonka series. Inexpensive, durable, and not as damaging when wielded like a tool, battering ram, or other 5-year-old's-weapon of massive destruction.
Better yet, a fire truck pedal car. My 7-year-old grandson is still totally captivated by mine (I've let him play with it for years), and he can't hurt it ~ plus the parts are big enough to be easy to find if he could break them off.