RCBS makes dies, both in their 55000 series.
You can make Krop brass from 8x50R Lebel cases, but they will be short and likely need the rms bevelled;, brass available nowadays is not bevelled correctly.
Siamese brass is WIDE at the base; should be able to make it from .45-70. I tried using 7.62x54R casings and the base stretch was shocking! Thankfully I was loading VERY low pressure and the brass held it in.
Lee's Lebel dies are handy for necking and giving your forming brass that nice long slope to the shoulder. Cheaper than form dies, too.
Loads for both are in COTW.
Hope this helps.