Wheel Cylinder Replacement- Driverside Front

[JAM55]

1963 C10 SBW Stepside - Where do I start? I know you guys will encourage me to switch over to Disc's on the front but funds limit that choice at this time (maybe a winter project?). I started to remove the old wheel cylinder (it leaked) but when I got to the fastener that holds it in place, I cannot for the life of me get it loose. I tried heat, breakerbar, penetrating oil,etc... I believe I will need to cut it off and drill out with progessive drill sizes to remove the remainder of the fatener.
My question is: Does anyone know where I can locate a replacement part to mount the Wheel Cylinder? I have explored the internet and cannot find it anywhere. Not even a part number.... Any suggestions? Your help would be much appreciated! Thanks

Oh ya, I broke the old wheel cylider off from the lug