I have an older wash that I need to do some masonry work on. I need to replace an entire section of concrete blocks. Unfortunately the original blocks are colored and not available any more. I was thinking of using concrete stain to match the blocks as close as I can. I have no experience with concrete stain. I am looking for input from people with concrete stain experience. Does the stain hold up in a carwash environment? Do you think this is something I can match pretty close? Any recommendations on types or brands of stains?