Quoted from Kneissl:https://www.flippers.com/coil-resistance.html
You can maybe ball park your way to a good replacement with this or something similar, check resistance and maybe the # of windings can be found for the Heighway coil? I forget if they were labeled.
Well, interestingly, I did a swap out for the newest I/O board that I received recently and did some test plays with the glass off...and, wouldn't you know it...not perfect, but much better performance to that right upper flipper. Made it up the ramp 30% of the time (which beats <5% of the time)... temperamental I/O boards I tell ya...but a definite difference.
Thanks for your comment to the flipper coils, I will look into that.
That said, it would be nice to see what folks are exchanging their CO10 flipper coils for when replacement is needed since it seems those could are no longer obtainable.