Chrysler was the first company to introduce power steering on their cars. This was in 1951. The 1951 and 52 steering boxes should fit your car.
Having said that, this first effort at power steering was on the lousy side. It had a lot of play built in that cannot be eliminated. Factory specs on a brand new car called for 4 inches movement at the steering wheel before anything happened up front. 1/8 turn is not unusual.
They have a steering box that goes fore and aft not side to side. The last vehicle I know of that had the same style steering box is a 1985 4 wheel drive Toyota pickup truck. A clever mechanic might be able to adapt one - for a price.
Now may I make a suggestion? You really don't need power steering if everything is working right.
Check over the front end and replace any parts that are worn or binding. Don't overlook the idler arm. Replace all 4 shock absorbers if they have over 20,000 miles on them.
Now go to a good front shop and get an alignment done.
You will find the car's steering, ride and handling are transformed. No kidding, others who have taken this advice were flabbergasted by the improvement.
By the way you will have to do the above anyway if you convert to power steering. Why not do it first and possibly save hundreds or possibly thousands of $$$$ bucks?
When your car was new little old ladies drove them. The only time you might notice a little too much effort is when parking. But if you make sure the car is moving when you turn the wheel it should not be a problem.
One more thing, if the steering still requires too much effort and you have radial tires pump them up to 32 pounds. This alone will cut steering effort by more than half.