That O ring you mention has been updated and the superseded part is made of viton, which doesnt shrink or wear with age.
The clamp you mention always must be the original spring type clamp and never a screw type (it will leak after a heating cycle)
Troubleshooting any power steering is very easy if you own a handy vacuum pump and a small pump and cork to pressurize the intake side. Basic hydraulics repair.
Tip:
Never use cheapass generic hose for your power steering intake or return side. Only use genuine parts for them along with genuine spring clamps.
And never use any oil other than Honda PSF in it, and remember to change the oil every 3 years or 50,000 kms,
Never keep driving your car with bad alignment as it will overheat the power steering oil very badly to the point of failure.