Ways to get good DA bits?

Pretty much the title. I'm making a successor chapter, and I need some good bits, mostly for infantry and espcially my chapter master.

I've got Company Veterans box some time ago, and those were awesome, but I'm running out of those bits and it's not easy getting another.

Bought a Ravenwing Bike Squad a few days ago so I'm looking forward to those ravenwing upgrades.

New upgrade sprues are awesome too, but I lost them and I think they'll show up as soon as a new one is purchased...

A box of ICC was bought purely for bits.

Not currently looking at 3rd party stuff now and I live in a non-american/eu/oceania country, so easier for foreigners to get their hands on, the better.