I have the numbers off of the back of the siding, but the local Lowe's and the local Home Depot don't have a way to match them up. I'm trying to find a few replacement pieces to fix some holes I have in the siding. Is there a source online or otherwise that can help me match texture/color/size my siding?
The best bet to find matching siding is to call or visit a local building supply store, not a big-box retailer. Give them any identifying information you may be able to come up with from the siding you've got. Even better is if you can bring in a sample of the siding itself.
We originally purchased vinyl siding on our garage more than 25 years ago from a big-box home improvement center. When we went to purchase more last summer (we had actually kept the labeling from one of the original boxes) we discovered that our local big-box stores couldn't help us even with the label.
At a local building supply store, however, they took one look at the label and told us exactly what we needed, even though the company name and color name had changed. They had what we needed in stock and we took it home that day.
Fortunately, the new version of the color we were after is a little bit lighter than the original version so what we're putting up now matches pretty closely to the color of the original, even with 25 years of fading in the sun. This may or may not be the case for your color.