i think there are photos of the real redman u-81 jones picklefork along with the karelsen redman u-8 in the NEWTONMARINE.SMUGMUG.COM photo galleries.
also check the chrisdenslow smugmug.com photo gallery.
i have the newton no. 101-I redman u-8 karelsen paint sheet and no paint codes listed. just the words red, white, dark green and notation about indian head logo found on redman chewing tobacco pkg. i think the tobacco pkg colors would be a relatively easy match.
the photos of the 2 boats side-by-side show same colors on each boat, in my opinion. you'll probably need good photos and / or the newton 108 - ? paint sheet for the graphics details, for a true scale model.
a friend built a nice gas thunderboat redman u-8 using krylon red, white and dark green with graphics from jim gieger.
good luck