Need help with parts!

Hi!

Im about to change my front drumbrakes to disc.
I have all the parts for the exchange except for the discs and calipers, does anyone know someone who sells discs and calipers with 4" bolt circle that will fit original spindels ?

MPBrakes had the things but with 4 ½" bolt cirlce, can one change the bolt cirlce by myself ?


//Chrippa