Put your own buckle in there. Why is this a problem? I have several otherwise ordinary Hog outfits except for the buckle, stainless steel, in the left shoulder loop. I do this because my left shoulder was badly damaged in a motorcycle accident many, many years ago and has limited movement in some directions. The added buckle makes it very easy to get into and out of my harness withlout having to flex my shoulder. I like it, I don't care if others do or not. I have been diving long enough to know what works and when there is justification for it.
For many years conventional harness rigs had snaps, twist locks or buckles in the left shoulder. If it were to come loose it is not problem and will not result in loss of control of your rig. If you want one then put it in, you may need to start over with a fresh piece of webbing however since you will need at least six inches of overlap or maybe a bit more to get the buckle in and have sufficient grip.
If you go with snaps you will need three heavy duty marine snaps, if you use twist locks you can find them at awning shops and marine suppliers, you will need two sets. A stainless or plastic buckle works well for me. Good luck.
N