I know this post is a little late but I just joined.
You can order parts for a lot of Porter Cable, DeWalt. Delta, and Black & Decker straight from DeWalt.
Go to
www.dewaltservicenet.com/ServiceNet/Logon.asp. You will have to register. After that, you need to know your tool model number (and if its a DeWalt, you may need to look on the ID tag to determine if its Type 1, 2, etc). You may have to go through the tool categories to find what you need. As for ROS sanders, the scroll down lists "sanders, orbital" and " Orbital sanders", and "Sanders". You may need to click each category and then try your tool model to find the right one. This will give you an illustrated parts breakdown. Then you need to do a search for the part. If they have it, you can order it. (As you can see, the site isn't real user-friendly, but it gets easier after a visit or two).
I just ordered a dust shroud and new pad for a DW421 to upgrade my old DW420 to vacuum. Cost me less than $30 and I had the parts in 4 days (that included a weekend).
If the above url doesn't work, Go to
www.dewalt.com, click on the Services & Support tab, and then click on the ServiceNet line about mid-page.
Hope this helps someone.
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