OK, let me get this straight: £6k or $10, 100 for a CASEBACK.
Not £6k for neat vintage miniature machine full of springs and gears and jewels, engineered to tiny tolerances and assembled by hand in Switzerland then housed in a fully waterproof case that's been machined and/or stamped from a single block of metal and graced with an iconic dial and handset that tells the time to within carefully prescribed parameters. Oh, and a strap or bracelet to affix said item to your wrist and some military provenance (however sketchy).
No.
What we have here is a single disc of 316L stainless steel. Nnot even the dearer 904L that Rolex now use, although at this level a price differential of x20 wouldn't add that much to the overall cost (I believe it's more like only 50% more). The whole thing is maybe <2" diameter with a screw thread, gasket (?) and some markings on. That's it. Think of it as a coin, if you will. A coin that's worth about 3 months' pay for the "average" British worker.
I'm currently wearing my PRS-82. Bloody good value Eddie.