I like Silca pumps on that era bike. The silca's came with their own plastic head that fitted the frame tube shape. The interchangable heads were a vast improvement but their length was very similar to the original silca end. You wouldn't need a longer pump body.

The older silca pump handles were round and fitted a clamp on pump peg or Campagnolo pump 'umbrella'. It was easier to buy a shorter pump and position the peg/umbrella to suit your pump. The older pump with an umbrella on each frame would allow one pump to be used for all your bikes.

Later model pumps had a tube shaped groove in the pump handle. You had to be more precise when buying a pump. These pump handles do, however, have provision to fit a pump peg on the top of the handle.

I fit a small piece of foam rubber between the pump and the painted frame. I tell myself this helps protect the paint (but it probably doesn't).