Laurie, how are you figuring that it's '63, just asking.
This stamp was printed in 55 different hues/shades, all depending on the year and part of the year. The shades are well documented.
From your image, it's not possible for anyone to know the actual shade/hue of this stamp. But from what I've learned about this issue, and I've studied it for a good 7-8 years now, most of the muted, lighter hues were later in the years rather than earlier. '65 - '67 are where we find more dull and pale colors.
So, I thought I'd toss that out there....I've got at least 75 covers with the 1863 date, many late October, November, and nothing with a stamp with a color as light as your image.... BUT, I do have them in '65 and '66 with colors that light.
My guess is '65 or '66....hope this is helpful, Ray
Hi Ray Mac I got the Scott colour chart for this stamp and it matches the rose that was used for the printing from mid 1862 to the next change of colour. Same with me I have over 300 stamps 64 and 65 all different colours! Cheers