Our red oak floors were finished 15 years ago with an oil-based polyurethane. (A poly that had a solvent content and required mineral spirits to clean up.) I need to replace one or two boards but I really don't want the smell and slow dry of the oil-based finish. Do you think I can use a water-borne poly on those boards without them being really conspicuous? Thanks.

After 15 years you will have a change of color to the wood, so even using the same finish will give you a different color. There are water based finishes that can be colored with powdered dyes to get the look of oil based poly. There is also an emulsion finish that dries with a yellow color. Light and time will help to even out the color. A couple of boards will not have too strong of an odor if you can get good ventilation.