Good Day,
Have an update to this adventure. Using the Parts Catalogue I found the part # for the current lights is 513936. I ran that number on Google and found Out of Doors Mart or
www.odmrv.com
They have my cool white light and interestingly, they note my light/part # replaces the 512718 part (warm LED) on High Sky RV Parts; in short, a match of two lights, both cool and warm.
After all that, and with some digging, leave it to the Airstream Forum to provide more info as found those who used lighting gel to change from cool to warm by simply cutting a disc-shaped piece of gel and insert inside the lens cover. I'll post the link to that thread when I find it again.