Does anyone have an idea where I can get the right titanium paint to match my tank?

I'd just find a paint supplier, they'll mix the correct colour and supply it in a rattle can.

I remember seeing all the actual paint codes on a thread here a long time ago.

Have a search - if you find the code any paint shop can make it up for you.

Hope this works:
https://www.dropbox.com/s/d92sxzy0l7yc6 ... 0.pdf?dl=0