Need Help With Medieval Austria Coins Authenticate

From the mint marks these appear to be for Silesia.

Upper left: KM 471

Upper right: KM 687 (There are several legend split variations. This matches the legend split for one of my 1708 FN 3 Kreuzer coins.)

Lower: Probably KM 471 (Krause doesn't list the letters, but that is my attribution for my 1695 MWM 3 Kreuzer.)

@kyp1891, you have a very nice group of Austrian coins. The method of manufacture seems to elongate them slightly sometimes. I don't see anything that concerns me about the authenticity of these, but as @MF2020 points out, everything is on the table for being faked at this point. If you wanted to pursue this further, you could measure the specific gravity or get confirmation that they actually are silver (e.g. via XRF). Of course these tests are not conclusive either, but would give you some added certainty.