Found it! BALLY FIREBALL CLASSIC. MUSHROOM BUMPER.......

[new forest pinball]

Hi all,
Some of you may know we are currently repairing a rare Bally wulff fireball classic. A common operator fix was to replace the yellow centre mushroom bumper with a standard stand up target, due to the bumper body receiving some real power shots and always breaking!

Has anyone got a complete mushroom bumper hanging around someplace please? Maybe from an old e.m. Can get a yellow mushroom cap ok but the bodies are tougher to find...any help greatly appreciated as when it comes to e.m. Machine parts we are completely "doofus".....
Looks like this!..........Cheers Keef.......

 

[astyy]

Keef the body contains 5 parts inc. the bottom nut + a standard rubber. If no joy in the UK this complete one on ebay.com for some reason the rubbers on these decompose and stick like sh*t is a git to remove, which is what I think is showing on that one;
https://www.ebay.com/itm/Bally-EM-P...ushroom-Bumper-Assembly-C-617-8-/274171042027

Dunno why these went out of favour far more interesting than a stand up target imho. Good luck with search fella

Parts breakdown on mine (+ nut)

Unhelpful picture of exactly what you need but sadly in use - yes 1 greedy EM can use 10.

 

[new forest pinball]

Thanks for the reply @astyy , found a second hand one on eBay USA......