I have no direct experience with S3 Spiders but I think the ignition is similar to L-Jet V6's - GTV6's & Milano's. If so, any low impedance coil should work such as an MSD Blaster coil. But why don't you check out Rock Auto as they may have a suitable coil for less. You could also try other Alfa parts suppliers such as DiFatta Brothers, Alfa Parts, Trail Auto, Alfissimo, etc.
76 Suzuki GT500
2011 Jaguar XKR
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