Lathe chuck jaws

[Wongster]

Hi folks,

Probably a silly question as I do not have other chucks to compare with. 

Are lathe chuck jaws of the same size chuck (say 100mm 4 jaw self centering chuck from Rohm) the same? I'm looking to purchase those jaws which has a master and soft jaw on top (bolted on). Can't find information on the same chuck I'm using online to figure things out. 

Wrote to Proxxon and they quoted me 2 brands: Mexpol and Rohm. I told them it's for the 4-jaw self centering chuck I bought from them. 

Is it possible to make my own set of master jaws? How do I figure out the dimensions of the "patterns" that ride on the scroll if it says possible?

Thank you. 
Wongster