By "flat top" do you mean suitable for the SSC P7 ?
Dont have any for a Mag D but I have a Mag C flat top HS brought it from 4Sevens
I have spare H22A HS for Cree LEDs, Mag D and Mag C
Just found a Britelumens HS for a SST-50 ... a SST50 of unknown bin is installed
on it. Also have a Britelumens P7 HS with P7 and burnt out driver installed
If anything there interests you gimme a shout