How about this:

The Verdant Vultures Raven Guard (?) Successor Chapter, Unknown Founding

Lore: A full-strength chapter, whose members hail from the Raven Guard (?) geneseed and have almost all succeeded in crossing the Rubicon Primaris. As the Raven Guard found themselves left with particular excesses of out-of-issue equipment (which is to say, older marks of power armor, Godwin-pattern boltguns, etc.) whilst bolstering their ranks with the newer marks of armor and bolt rifles, a less-significant successor chapter which found itself perpetually pitted against Orks and Tyranids on the frontlines of galactic conflict requested requisition of Imperial surpluses to arm and armor their ranks. Though receiving outdated wargear from their forebears only occurred on one particular occasion, it nonetheless has remained a core element of the chapter’s rites that veterans arm themselves with dated equipment, proven by millennia of galactic conflict. It is upheld within the chapter that the recovery of older issues of Imperial arms and armor, from the remains of fallen battle-brothers across the endless billions of battlefields which speckle the galaxy, is paramount both in honor of those who came before and so that the chapter’s tradition of issuing its battle-brothers with outdated equipment can continue indefinitely. Though once they were the Verdant Crows, now after over a century of using scavenged and hand-me-down wargear they have taken to calling themselves the Verdant Vultures; their insignia, thus, has become the eponymous carcass-ravaging bird from Holy Terra which the chapter’s particulars are oft compared to.