I'm about to tackle this myself - I'm working with the Pinscape build guide and there's a whole section on options for force feedback: http://mjrnet.org/pinscape/BuildGuideV2/BuildGuide.php?sid=feedbackDevices

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There's a separate page just for solenoid devices at http://mjrnet.org/pinscape/BuildGuideV2/BuildGuide.php?sid=contactors which proposes four different options:

- Contactors / Relays

- Automotive starter relays

- Real pinball solenoid assemblies

- Open-frame solenoids

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As the author suggested on that page re: automotive relays, I'm ordering a pair of Ford SW3 starter relays <https://www.amazon.com/gp/product/B07GR4G5XC> to test the waters, since I have a spare desktop computer power supply on hand and the SW3 relay operates on +12V. Also they're pretty cheap at $9-10 each and I have free returns through Amazon Prime. That should give me something to play with while I'm setting the rest of my cabinet up before I go all-out on a full DOF system.