I actually just finished my Captain Jack costume. I had the jacket made for me so good thing you have yours alreayd cause I can't help there. Also if you wanted some RAF buttons I know ebay usually have Kings Crown buttons and sometimes you can get a large lot for a decent cost. Also I can't look at images here at work so I will check them out when I get home.
As far as the Time Vortex Manipulator goes I acutally bought mine. There was a Dr Who toy one that was released in the UK and I bought it off a UK collector... I know I saw a thread somewhere (not here I think) about someone who built one... let me see if I can find it.
I am not sure if this thread will help as I didn't read past the first couple pages and saw some diagrams and chatter about making it http://www.therpf.com/f9/doctor-who-...spoiler-89715/
Maybe you can find one of the toy ones they made but they seem to be getting harder to find. Worst case take a lot of pictures of it to a leather worker and have that part made and try and build the center piece?
Sorry I am not that helpful! I did take the easy way out after all.
If David Tennant ever asked me to run away with him I would. I do not think I could ever say no to that man!
Captain Jack Harkness (Torchwood/Dr Who):100% Saturday and Sunday
Victor "Sully" Sullivan (Uncharted):100% Friday and Monday