Triangle (Delta) chord symbol

[dflat]

Is ir possible to write C7M instead C^ ?

Do you mean would the player know what it is? If you put it in, it would probably show an error when it goes to play it. You could write in C^ in the measure so the player knows what to do, and add C7M either as an alt chord or text.
Obviously if you are not using the player it will input, but might not show in the chart fonts we use.