I’m surprised that more models from the Adeptus Ministorum were not released. Drill Abbot Josef was released with the launch of the game, but nothing else was released (except a model from the adeptus sororitas, and even she was a sister repentia and not a sister of battle). I think Josef is a tricky model to use as a conversion. His torso and legs don’t naturally fit the proportions of other inquisitor bits, though i applaud GW for making a model with a beer gut.
And there are some models of other ranges that can be re-purposed for 40k.