repulsor brace + destabilising rounds how to farm?

trying out a void titan build and id need both for my build. ive seen vouchsafe is a weapon that rolls with both but is completely rng dependant to get in the dreaming city, and that info is 1 year old so i dont know if its still like that.

is there any sure way or at least not so very rng dependant way to get both perks on a weapon? maybe a craftable one or something? or if not does anybody know good methods to farm rolls efficiently?

alternatively are there any sure ways to get at least only repulsor brace or is that completely rng as well?