Stamping steel or other hard material are not easy.
There are a lot of practice required before you can achieve good impression at all time.
Anyhow, I offer to make steel stamps out of H13 tool steel material.
The stamps will be made with about 75 mm shank and heat treated to about 52 - 54 HRc
The stamp is designed to stamp on fully annealed steel, it also can be used to stamp on steel at forging heat (red hot).
The pricing will depend on the total surface area of the stamp.
Generally it will be about $200 for 100mm˛
Click here for Information on image requirements for your stencils and stamps
Here are some sample of the steel stamps I made.