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Rampinelli (REG) and Arregui (ZEUS) did covers which fit just fine.
In Rampinelli there are something like four to six colours. The have a dimple for the thumb.
Arregui had early and late type, early type resembles a cough lozenge and late type has a waffle pattern.
Six or eight colours were offered through the years.
Freres Huret made them in natural rubber - an off-white colour, but the opening is a bit small to accept a Campag or Zeus lever. Might be difficult to mount without tearing.
REG Nr. 341 -
ZEUS early type REF. 18 -
This site shows Campag ~30USD, REG ~15-20USD & ZEUS ~20USD -
https://picclick.com/REG-shift-lever...853644215.html
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BTW - Campag were made in more than just the blue colour, although blue was the "default."
some of the other colours included white, dark green, red and yellow.
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