Looking for an MC Rebuild kit 1 inch bore.

I am looking for a master cylinder rebuild kit for a 71 CS with Power Drum Brakes (no disk).
The manual indicates that I have a delco morane MC with a 1 inch bore.
The MC on my car is factory original.
Most of the stores / web that sell replacement kits do not post the bore size.
A friend of mine doing the rebuild just bought a kit and got the 1- 1/8 bore, which we found out later is only for the cars with Front disk/Rear drum.

Suggestions welcome.

 

from rockauto $22

RAYBESTOS Part # MK497 Professional Grade; 1" Bore
Front Disc brakes; Rear Drum brakes; Manual brakes; Repairs OEM Cylinder Only

 

Thanks Retro,
I did find the #MK497 on the Raybestos web site, but could not find the bore size on the specification. Interesting the Rock Auto has the bore size clearly listed.
Thanks.

 

I bought a Master Cylinder rebuild kit from Rock auto with a 1” bore for my 71 CS power drum setup.
The kit had springs, gaskets and one Primary piston.
The kit does not include a Secondary piston.

My existing Secondary piston (aluminum) is all pitted. See attached pictures.

The question is, where do I get a Secondary piston with a 1” bore for my 71 CS?

Rock Auto does not carry them.

Below is a picture of my Secondary Piston. Notice the pitting.

 

orially has rebuilt units you can use the rebuilt unit are if u want to keep your original unit u can maybe swap the parts from the meman. unit to your original unit. these units are cheap like 20.00 to 30.00 a peace. just an idea I thought of running by u hope this helps
thanks ray

 

I may have to just buy a whole rebuilt MC with a 1 inch bore and remove the parts to put into mine.

 

I did end up buying a full MC and then removed the parts and put them in my original MC.
The new parts were identical.
Now I just need to paint and install and see whathappens.

Moral of the story, If you want to rebuild your old MC, just by a new one and swap the parts.

 

Oooo and by the way thanks for the idea ray
glad i could help
ray

 

of course Ray, thank you for the suggestions.
This forum has answered many of my questions, just by reading what other have done the past.

Can't wait for spring.