Which MC for Front Disc/Rear Drum Conversion?

[Brandon]

I have converted my '69 Camaro Manual Drum/Drum over to Disc/Drum. I now need a master cylinder that will work. When I hit the brake pedal, it is really stiff and just barely stops the car! I cannot lock the brake if my life depended on it (and it probably does)!!!

I will keep the brakes manual for now but will upgrade to C4 front discs and 4th Gen rears later. I just need a cheap manual M/C to add now until then.

Thanks,
Brandon

PS
Sorry if this has been covered already. I didn't find an answer with part numbers.