You would need to ask them. Perhaps it is not a colour they have traditionally used.
I would hope they would want to work with you to get the outcome you want, but at the same time I would be guided to getting a style reflective of what could have been done at the time the frame was made.
If you look at the 1966 catalogue the original finish was one specified by the purchaser.

I wanted a magenta in the flamboyant (semi-transparent so the silver shines through) to be identical to the original 1952 finish, but in the modern 2-pac paints they discontinued the base needed for the magenta as it faded far too quickly and there were lots of disappointed customers. So I opted for the polychromatic magenta for the spearpoints.