The small teklok will allow you to carry it straight up, 45* cross draw or horizontal. The spacing is tight and the screws *just* make it. You'll only be able to get two screws in and use the rubber washers.
Other than that, I ran beaded chain through some paracord jacket and hung it around my neck. I put a firesteel, whistle, keychain compass and LED microlight on the same and put a couple ranger bands on them to keep them from rattling.
I've experimented with hanging small knives upside down on my pack shoulder strap. Zip ties are great for that. The Becker Necker is a natural to do that with and it worked well with the SAK Trekker using one of On/Scene Tactical's kydex sheaths. You can zip tie pouch type sheaths on your pack strap that way too.