How would you go about removing the bombs from this arm? I assume that the metal pin is simply just an insert and the bombs are pressed onto the pin. But after applying enough pressure between the arm and the bomb to try and pry it off ...the arm keeps bending and I don't want it to break if indeed there is some other way I should be attempting to remove it.

Your helpful insight is highly appreciated!

You need to apply heat to the pin to soften up the plastic. I just can't recall what kind of tool is used to apply the heat.

soldering iron, commonly used in electronics. Considering how soft the plastic on the arm is, it may rip through the plastic on the arm as well. It'll heat up all the plastic that's in contact with the metal. It's too bad you don't have a tiny set of grippers attached to your soldering iron to pull the pin out of the bomb rather than pulling the bomb out of the arm.
The alternative is you could just hack off the bomb. It'd save the arm, but the bomb would be unusable for anything else, as you'd probably be ripping it to shreds, not being able to cut through the pin. (unless you have a dremel/saw that can cut through metal)
I'm not really sure how much it would damage the arm. I think it would probably just tear the ring that holds the head of the pin in place, leaving a much larger hole. The ring may be thick enough to hold the pin though, so it may just get squished before the bomb gives way to the pin.

RX9:

I think this would probably be easiest. If one wanted to save both, the easiest course would be to buy another Ransack, cut up the arm of one and the bomb of another, and save the good part from each. It should be pretty simple to pull the pin out of the bomb after it's cut free from the arm.

It might be possible to drill a small, unobtrusive hole through the bottom, between the two bombs, to get at the pin with a punch.