Are these available anywhere?
I'd just find a condenser. 1 microfarad.
The basic
suppressor for the
ignition system is a 1 mfd
suppressor. Attach it to the LT or positive (+) terminal of the coil on the
ignition switch side. There are two types of
suppressor connected in different ways, depending on whether your set has AM or FM reception.
https://www.summitracing.com/parts/smp-rc1#overview