The smallest active setup for Schoeps is the genuine product from Schoeps.
You can order any part from Posthorn, or the US distributor, and it can be serviced with common tools. Schoeps has been listing all of the parts on their price list, including a blown-apart drawing showing all of them, for years. You can buy any or all of the parts. They'll likely do that forever. If a cable gets ripped out, it's likely just a $20 part. I've never had that happen - it's a very stout part. But I have spares on hand, so I can fix them anytime without missing a show.
Last time I looked at the price list, the capsule end parts were $317 per channel. You would just need to add cable to that. That is not trivial, but it ain't rocket science.