MC pushrod parts needed

That's a pretty good idea except the hose may not last long. Now, a nylon tube would work;the kind they use in pressure systems. Or a square section O-ring cut to fit, say from an old caliper piston(do not oil it!)
I suppose your idea would work, until it got brake fluid on it.
Whatever you use, do not oil it.Use the silicon O-ring lube, if you have to.