I think the key to getting a sheath is patience and determination. Know what you want and just keep at it. For example, last week I picked up the sheath I was looking for on Wednesday morning (the day after). Either everyone forgot the alphabet, or it wasn't something anyone else was looking for and it was there for me to buy. Other sheaths I've stalked at 9pm and missed a week then got one the next week. One maker versus dozens and dozens of buyers isn't even or even close to perfect, but it does work. And most of the major buyers do miss a week here and there, read the threads 1/2-1hour later when someone just got online. Also, people let go of sheaths in the flea market regularly leaving another way to pick them up. Everything selling out every week is great for us and even better for Bud. Leftovers are the death of makers, retailers, car dealers, etc., essentially wasted capital stuck in merchandise no-one wants.
I for one wouldn't want my every whim sheath on demand when I could have it as it would undermine the handmade individuality of each sheath option Bud chooses to make. A few week wait is worth the quality provided. I recently acquired an older (3YO) heavily used sheath I received with a knife purchase. A little TLC and it's new again, a testament to the craftsmanship and quality of the original product. Good luck in your hunt.