I agree with Chuck. You could match using something like Trans Tint, but the color will change with the age, and the patina of the new pieces as it changes. Those new pieces will eventually darken down no matter what you do to match them to the existing floor.
I would let them know up front that you will match the color as best you can, but that it will change in the future and you can't be held responsible. The only real solution, Nick, is to sand it all down and finish it the same.
Hi, sorry I missed you. I have gone to find myself, but if I return before I get back, please ask me to wait.
Nothing ever gets built on schedule or within budget.
Tool Storage Bait and Tackle, LLC.