Me239:
Welcome to the forum. The Bianchi Viper is a ballistic nylon, vertical shoulder holster that might meet your needs. One advantage of it is that the right sized holster will fit 2.5 inch, 3.0 inch, and 4.0 inch revolvers and medium framed semi-autos (H&K P7, S&W 6906, M&P 40C, etc.) You can usually buy them new/unused off the on-line auction site whose name rhymes with "flea-bay". The Ken Null "City Slicker" is size specific (J-frame holsters for J-frame revolvers) but have the advantages of very modern, and excellent design, fast to get into action, and one size holster will fit all barrel lengths. The Bianchi 9R has been out of production for at least 20 years, but are still very popular. They can be found frequently on "flea bay" but usually sell quickly, and at outrageously high prices ($100+). One big advantage of the 9R is that some version were made with belt slots, so you could remove the shoulder straps and use it as a belt holster if desired. If you get the one sized for ".38 and .357 Magnum revolvers, it will hold 2.0 inch J-frames as well as 2.5 inch barreled K-frames (Model 19/66). It is an inverted, vertical shoulder holster that I really enjoy. Also, because of the design, I can draw left-handed from it, if I have to. If you like that inverted shoulder holster design, Safariland used to make a Model 19 for 3.0 - 4.0 inch barreled K-frames that can usually be found at reasonable cost at "flea bay".
Hope this helps.
Regards,
Dave