Hydroboost: master cylinder change?

Hi all, I was thinking about adding a hydroboost system to my 69 RR. It currently has the stock manual/all drums master cylinder, but I just changed the front drums to disc brakes.

I also changed from manual steering to a P.S. column, and would like some hydroboost stopping power from that. My question is: Should I use the stock master cylinder w/ hydroboost or do you recommend I buy a different one (like Wilwood MS) ? Is the stock MS dangerous because of it's age or stock bore size, etc?
Also, I included a picture of the engine bay just in case.

Thanks for the help!

You need a disc/drum master cylinder. Not sure on size but it needs to be for the correct brake type.