Whilst fleshing out my homebrew Chapter of Space Marines I came across a bit of a problem. My Chapter has access to a forgeworld run by the Mechanicus and maintains very close ties with them, but not Iron Hands close. They specialize in shock assaults, armored assaults and some sneakiness. I would like them to have access to Imperial Jetbikes, but they are descendants of the Imperial Fists and "technically" wouldn't have those shiny, floating bicycles of doom.
Originally I had thought to write about a vault being discovered within their sector containing the STC and then voila! It belongs to the Chapter. But that's boring and I don't want these guys to be overpowered (later in the fluff they get invaded by a Chaos Warband). Plus, I want to write an interesting story.
So I was thinking that they came into contact with a Rogue Trader who went treasure hunting or something, found the STC and is trying to hand it off to the highest bidder instead of straight to the Mechanicus. Thus, the Chapter hacks into the Rogue Trader fleet via their Techmarine buddies, boards the ships, grabs the STC, blows up the ship and gives it to the Mechanicus who then provide them with Jetbikes.
I have basic knowledge of Rogue Traders and more knowledge regarding the Mechanicus, but I would still like to read into both more. The Rogue Trader Fleet would have a Letter of Marque instead of a Warrant of Trade to make them less powerful or protected by the Imperium.
If the Inquisition comes knocking on my Chapter's door I would be fine with that. I don't want them to become renegades or traitor marines, just opportunists
So is it plausible fluff? Comments and criticism are welcome.