1964-D Washington Quarter. Think It's Finally A DDR

Yes that steplike doubling looks like Machine Doubling to me too. On the other hand, the coin is silver so it is still worth keeping.

Note the affected areas:
1. Machine Doubling affects the outside/inside edges of the devices.
A doubled die show spread in the centers of the devices.
2. Die wear will show on the outside/inside edges of devices in the direction of the closest rim.
A doubled can will always show a spread in the centers of the devices, sometimes showing a split serif on the corners of the devices.
So there is no need to look for a doubled dies on the outside/inside edges of the devices. Look for the spread instead. Don't seen anything there? Move on to the next coin.
3. Machine Doubling removes the contour on the outside/inside edges of the coin, leaving them flat and showing a 90 degree edge where the push ended.
So when searching for doubled dies, look for the spread or distortion on the single squeeze dies, and forget looking at the outside edges of devices.

Seeing images side by side with a normal coin will help you see if the devices are enlarged or not. Also look at the centers of the devices of closed letters. On these a doubled die will have a smaller opened area because of the spread of the devices. Note this on the image above. Doubled dies are hard to find, but Machine Doubling is common to find. It alters normal die cents and doubled die cents as well.

Here is an example of MD on a doubled die. Note the date is a doubled die, and the mintmark is normal. (That is because the die creation is one process and the adding of the mintmark back then was a second step. Thus when you see MD on both the date and the mintmark in the same direction, it is Machine Doubling.) Thus look at the yellow arrows on these coins. All are showing the doubled die on the date, but note the affect the Machine Doubling has on these coins? Note the Machine Doubling is in the same direction. So what do learn? That Machine Doubling can happen on doubled dies and regular dies. But Machine Doubling never creates a doubled die. A doubled die comes from a die that has hub doubling on it. They are struck doubled die, but the machine can alter the devices post strike. (true variety collectors prefer to not have Machine Doubling on a doubled die, as it just adds confusion to that die when taking images.)

CoopHome: Will Machine Doubling make it a doubled die? no. a doubled die is from a doubled die. Machine Doubling happens post strike.

could this also be an example of 'push doubling'?

Machine Doubling works for me.