Same thing here
Same thing happened to me a two or three years ago. I was able to find them by borrowing a friends scuba gear. There's a couple of tabs that hold the inserts in the sleeve, in my case one had broken off allowing them to fall out. At the time I called Hood, they no longer had the inserts but did have a replacement swivel. Can't remember the price but I ended up putting the old ones back in held in place with a couple of short stainless sheet metal screws run through the swivel & into the inserts. Been there for at least two years now but I do check them every once in awhile. Oh yeah, I dabbed a little epoxy on the screw heads to help hold them in.Hope that helps.Ron