Wiper switch on dash

My wiper switch (the little round knob on the dashbaord, just above the speedometer) is stuck "on," and I had to pull the fuse to turn them off. I am going to squirt some electronic cleaner into it, but if that does not work, replace it. Here is the problem, Pelican (and the other usual places) only seem to offer the following wiper switch:
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Windshield Wiper Switches
Replacement is fairly easy and straightforward, but requires steering wheel removal.

Windshield Wiper Switch, 911 (1974-75)
C-613-306-01 CALL
Windshield Wiper Switch, 911 & Turbo (1976-89)
C-613-306-02 $137.20
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This is obviously the steering column switch, not the little knob on the dash. Does no one sell the latter?


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John C
1988 Carrera coupe
1957 Speedster replica
1997 A6 Avant

My parts book calls it:
Potentiometer - Intermittent Wipers

1974-75 911 618 147 00
1976-89 911 618 147 00

Hope this helps,

Tom