Thanks for all the replies. It does't seem to b e a critical issue so far as operation of brakes are concerned, I will order a keeper and replace it the next time I have the MC off the car. Which might be never.
Hahaha. So funny
This is where I learned about the vacuum tube.
We used to install.change/install headers in all types of vehicles.
I met my mentor at the strip where he and his pals were testing headers in his 64- 426 wedge Dodge, they were testing 3 sets.
On that car he taught me it was easier to install the fenderwell by moving the Master cyl outta the way, by pulling the pedal up outta the m/c., then 4 firewall nuts and move the m/c outta the way.
We damaged the rubber on the pushrod on several misc cars, and I had been taught to use the vac tube, didn't know there was a "special" rubber, figured it was like a cotter pin, if it worked, used it.
WELL I CAN TELL YOU - trying to pull that vacuum tube pushrod outta the Master cyl is every much as hard as any fkn factory special rubber.
Again. This is tested many times. Some cars with a roll bar can be bitchin to pull the pedal hard enuff, and the pushrod with factory rubber vs vac tube rubber is just as capable of pulling the guts outta the Masters !
Ooooh-oooh - it's not special factory.
Order it - wait a week cost $10 with shipping or walk over to the rack of vac tube, nip a bit off, grind a notch in the side. Chamfer ends