Buds stocks one in silver, however they are out currently. See link below.
budsgunshop.com/product_info.php/products_id/411558430/kimber+1911+22+lr++conversion+kit+silver

David, I would give these folks a call : https://xtremegunsandammo.com/shop/pistols/kimber-pistols-for-sale/kimber-1911-pistols/rimfire-trade/kimber-1911-rimfire-target-conversion-kit/

Hi, I saw two listing of the Kimber 1911 22lr conversion kit in (1)un(2)roker. Replace (1) with G and (2) with B. I hope this helps

Its available for backorder here
brownells.com/handgun-parts/slide-parts/caliber-conversion-kits/rimffire-target-conversion-kit-prod26573.aspx