It's not leather but the Uncle Mike's Korda nylon Large Frame Sidekick Hip Holster (size 53) is a perfect fit for my S&W 66-1 with a 6 1/8" barrel (measured from the cylinder face). It has a flap for retention and as you require, the trigger guard is completely covered. I bought mine for pretty much the same reasons that you are stating. When you read the product description be aware that their barrel measurements are made from the front of the revolver's frame. If your 608 barrel measures 6" +\- from the cylinder face, it should do the job! I got mine on Amazon.com for <$15. Good temp fix until you find a leather one.
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