Ok without much to go on here I have found two places that you might check in to. The first one I did not really look at but the second site has some promise and appears to have just a wide variety of all kinds of stuff (I know very technical of me) like pumps, filters etc. Since you know what your piece looks like you'll have much better luck looking at this site. I hope this helps.
www.partsdrop.com (Only have Xerox Parts)
www.directindustry.com (has a great selection of the sort of things we use in our hobby)
Good luck and let me know if either are helpful. If not I'll keep looking.