Lot of restorers and "refinishers" use alkanet root. It is the authentic red look. I mix a handful of the ground root into a 1.5 litre wine bottle full of tung oil/urethane mix and just leave it there soaking, refilling the tung oil mix as needed. I have a bottle I have used at least 6 or 7 years like that. The red color "just keeps going and going." I agree that the older Merkels and Sauers look great, and this finish emulates that look very well and wears great, and touches up easily. Be sure you label the wine bottle properly as to what is inside. It looks very much like a good rich Burgandy.