Hello, I'd like to get some help, about the compatibility of my fountain pens.

[Balance1]

Hi.
I want to get help from everyone who knows a lot.

I have a custom fountain pen that uses a Bock #6 250 nib.
But recently, I've been wanting to put a new nib on this custom fountain pen. 
I'd like to fit one of Omas' nibs, but I'm not sure which one to buy to match the specs.
For example, if I buy a nib from Paragon old/new, Milroad, etc., 
Which Omas' nib should I buy to be compatible with my custom fountain pen?

[Dione]

I wish you luck in finding any Omas nibs for sale now but I don't remember if the Paragon and the Milord both took the same size. I thought the Milord may have been a smaller version than the Paragon. Good luck. A 14ct version of a Bock or Jowo #6 might be easier to find if you want a gold nib.

[Balance1]

16 minutes ago, Dione said:

I wish you luck in finding any Omas nibs for sale now but I don't remember if the Paragon and the Milord both took the same size. I thought the Milord may have been a smaller version than the Paragon. Good luck. A 14ct version of a Bock or Jowo #6 might be easier to find if you want a gold nib.

Thanks so much for the info.  

I just got information that the new Milroad and the new Paragon nib are compatible.  

Not sure, but I'll try it.  

Thank you for wishing me luck.