The dipstick should be in a tube about halfway between the distributor and the starter, on the passenger's side of the engine. If ythe tube is there, but the stick is missing, just use any type of stiff wire to probe the tube and see if there's any evidence of oil in the engine. I can give you a ballpark guess about the right dipstick length by measuring one from one of the engines I've got in storage.
Your engine looks like a 1954-62 model, either 235 or 261 cubic inch.
Jerry
