What master cylinder for rear disc swap?

[BigRed76]

My '71 C10 is about to get all new brakes. Front will be stock rotors with '79 C30 calipers with 3 5/32" Pistons. Rear will be CaptainFab's D52 conversion with Astro rotors and '78 Eldorado calipers. I'll be keeping the stock booster, and as far as the prop. valve goes I'll be upgrading to the wilwood 260-11179, but I'm unsure on what master cylinder to use. The things I do know is the MC will need to be 1.125" bore (which is same as stock MC now), and it will obviously need a bigger reservoir than stock, but I haven't come across any master cylinders that specifically state they are for 4 wheel disc applications. I've been thinking about the wilwood 260-13270 MC, but don't wanna spend big bucks on a MC if I don't need to. Any thoughts are greatly appreciated. Thanks, Zach