It's always nice to found some alternative with modern elements. The characteristics are not exactly the sames, but the most important is that's works very well.
The datasheet of this coil can be easily found at the Guardian Elec. website. The resistance of the A-18102 is about 9 Ω, and the resistance of the 4HD-I-24V DC is about 18.9 Ω.
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This means that the new coil use less current. It's a good thing, because there is no need to change the transistor driver, nor the fuse. The counterpart is that the coil is (theoricaly) less powerful. But in practice, it works.
As far I see, on your Joker Poker, it is used on a 4-targets bank, so it's should be enough powerful for all other models.
Guardian says also, they can produce special coils/plunger on demand, but I'm not sure that is the case for this one. The plunger look to be the standard provide with this coil. A first glance, I believed that it was longer, but looking carefully at your picture, I'm now quite sure that it's not the case.
Don't know the meaning of W2 * 1286 on the label. May be a wire gauge (type/turns), or may be a stamp of made (like integrated circuits ? 1286 ~ week 12 of 1986 ?).