Need to find a 1 piece steel flat weaver type base and having trouble? Anyone know of a common model flat top receiver I can search for and just cut the thing to the length I want? Thanks in advance

I believe EGW makes a steel base blanks. They are a picatinny pattern and already cross slotted. Brownell’s carries them.
Brownell’s also has a Weaver pattern blank which does not have cross slots.
The only ready made Weaver dimension steel flat top base I can think of are Weaver Grand Slam or Warne Maxima lines (some of the Maxima bases are aluminum). I know one of them makes a base for the Marlin 336 which would be flat bottom.

Thanks found blanks you mentioned.