Here are some examples of holsters for the model 19 and 66 revolvers with 2 1/2" barrels. Their popularity is clear as I run into holsters made for them fairly frequently.
A Myres holster with hammer protector, kip glove leather lining, tie down holes and a heavy duty belt loop.
A Myres holster with the logo obliterated. I don't know if these were seconds but I've seen a number of Myres holsters with the logo scratched or burned off.
This is a holster stamped " K3" but no logo or makers mark. Pigskin lined, basket weave finish- I'm convinced it was made by El Paso Saddlery, even the K3 looks like their stamps.
A Myres IWB lined holster.
This is a Lawrence holster, size code 654 is for a 2 1/2" model 19.
A Myres thumb break holster, this is a later model and holster.
A Bianchi 9R2. Marked .38/.357 to indicate the 2 1/2" K frame. Note the Berns-Martin sticker on the inside.
Regards,
turnerriver