W. R. Brown diaphram air compressor parts???

I have been using a W. R. Brown, model 410 diaphram air compressor, trouble free, since the middle 1980s. It doesn't seem to be pushing as much air as it used to, so I would like to install a new diaphram.

After using all of the search engines that I know of, I cannot find a site for W. R. Brown or for their parent company, Intermatic Inc., as listed on the parts list. I can, however, find a reference to W. R. Brown as now being a division of Federal Equipment Co. When I go to their website, there is no reference to W. R. Brown or air compressors of any kind. What gives? There has to be someone out there making and/or selling replacement parts for these air compressors!

If anyone can help, please advise.

Thanks,
Pete