Source For Booster/Master

I only ask because I'm considering replacing my iron Master Cylinder with a later model aluminum unit. ... I'm just concerned about that stiff pedal issue.
I bought two "4 to 2 bolt adapter plates" recently on ebay ($30). You can use any 2-bolt aluminum MC with those. Many here like the late 80's Dodge truck MC. I have been buying the Breeze ABS MC to keep my old Mopars the same, and started with that on my Dart. I paid ~$25 ea for new ones on ebay. Look for an MC with 2-ports on the side you prefer (most ABS ones are 2-port). Also, better to stay pre ~2000 since many manufacturers switched to "bubble flares" then (can form w/ a dbl flarer, see youtube).

I don't follow the "awesome brakes" comment about an MC change. The MC simply produces fluid pressure. You have a choice between "easy pedal" with "more travel" and "hard pedal" with "little travel", depending on what bore size you select. The 7/8" D bore in the Breeze MC gives a little too strong braking with the power boosters in my 65 Dart and 65 Newport with their current drum brakes, though might be perfect with front disks (someday). The pedal travel is barely noticeable, and that is with DOT 5 which some (who never used it) claim is "too spongy".