The long wing isn't typical but the part looks more Martindale or Uvalde to me than Marshall.
Just a guess....john h
It's a very small piece to deal with but that long wing does it for me, I vote Marshall ( from the 7 foot deep Marshal clan )
I've had a few really tough hand digging deep test holes...The deeper I get the more I " Please Lord...DONT let me find ANYTHING down here "