Master cylinder rebuild kits?

[TubeTruck]

Are these possible to find for our trucks? Do I have to take mine apart to know what size it is? I've see some for specific bore sizes but I am unsure how to find one for my truck because most give different options. I came out yesterday morning to go to work and fired up my truck, smoke started pouring from under the hood. I popped the hood and didn't find anything until I started to drive, or more like stop. The pedal was almost to the floor. I checked the brake master and the rear reservoir was empty. Looks like it somehow jumped the frame rail and sprayed the header which is where the smoke was coming from. I picked up a new AC Delco master and will be installing that today but I want to rebuild my existing for a spare. This is the hydraboost master from a '79 K30. Any ideas?

 

[bucket]

I put master cylinder on my '79 K30 about 10 years ago. I specifically went to buy a rebuild kit but there didn't seem to be one available. So I got a new one for 35 bucks or so.

I'd be very surprised if a kit is offered now. Usually it's the other way around- they are available and then they are not.

 

[TubeTruck]

That's what I figured. I only paid $30 for the AC Delco one but don't want to spend that on a spare. If I can get a rebuild kit for $5-10 I'd go that route. Once the 454 goes in I'll be installing the newer hydraboost and master anyway.