Battlefleet Gothic Fleet advice

Howdy, I will be taking part in a campaign and we will be incorporating BFG into it.

So far I will be taking a Black Ship as my fluff reason for being there is that I will be escorting said Black Ship around the system.

My main army will be Militarum Tempestus. As our campaign progresses we will be purchasing more units and whatnot so I will be supplementing my army with Inquisitorial units and Imperial Knights.

Now my question: Which ship should I use for the Iknights?

Im not super good at keeping track of all the fluff intricacies, I just like to use the right things for the right things. I can only assume they use a large ship but wouldn't have a clue at which one.

I have access to all the BFG books so no need to post stats, just a name would suffice.

Thanks

Sorry mods, I think I may have put this in the wrong forum section.

There doesn't seem to be any canonical listing for Imperial Knights. Kind of unsurprising since their codex came after BFG was scrapped. Pick a smallish Mechanicus ship and say they use something similar to that?

Yeah that was my thoughts as well. I looked in the imperial ship book and there is only the one mechanicum ship so I guess its an easy choice. Thanks for the reply