Looking at the last picture you posted from above of your machine regarding the ball hop, it appears your ball guide is riding "up" a little bit. WCS does not have "typical" in lane ball guides, but rather, out lane style guides on the in lanes. Remove the right slingshot plastic (you have to remove a couple nuts, the lower piece of the ramp, and the coin flip guide, not too difficult) and see if you can't bend it down a little. Use a straight edge to check the alignment after to be sure its straight, and drop a couple balls through until the hop disappears. You probably shouldn't have to remove the guide.
Before throwing money chasing a problem on your machine, see if you can't determine the root cause of the problem and use the simplest fix (a broken connector that needs to be re-soldered, a mechanism that has worked it self loose and just needs to be re-tightened, a sticky switch or mechanism that has stopped or reduced functioning and just needs to be cleaned, a guide or rubber that needs adjustment, etc). From my experience, components rarely actually physically fail in machines, they just need some adjustment or persuasion. These are robust, commercial grade machines for the most part, and are generally built to take a beating. Always start with the simplest fix, and go from there.
Good luck, and happy flipping!