Tuning a veloce rear mech a special bolt sourcing question

[bm0p700f]

I was building up a bike today and I started to think about my nice winter bike as I was about to screw on the the veloce rear mech. I have a winter beater and a nice winter bike. The nice winter bike also has a veloce 10 speed 2012 mech.

It weighs 230g, it as a steel back plate. I though fibreltye do a 2g cage and 4g pulley's That would shed 30g. Alu bolts from toronto cycles would save some more and there is lots of scope for a bit of dremeling.

The question is there are two steel bolt that act as pivots in the pallallogram. If I do the whole bolt thing I would like to replace these two bolts as well. They take a T something torx (I forget which one now) and I think have a M4 thread at the end. Anyone come across any Ti bolts that would work. It think with a little bit of effort and not alot of expense a 180g mech is easily doable maybe less.