If the push rod has worn into the lever arm there will be a hollow which will stop the lever arm sliding easily against the push rod for future use. The easy solution is to get someone to use Stellite filler rod to weld up the hole. You then have to grind the filler back to the original shape. That is not a critical job and can be done by hand. If you are not familiar with Stellite then it is a series of materials which are hard and wear resistant. Different grades have different hardness and your welder, or someone on here, will be able to advise which grade to use.
