Scott, sending you a PM about Needlebar....will see if I can help you get in!
I don't know much about the Domestic machines other than they were bought out in 1924 by White, but they were maintained as a subsidiary (according to ISMACS)
I did find this website in a search....looks like the "D" on this page was made AFTER 1910, because of the last patent date on the machine:
http://www.kelsew.info/Domestic/dome...lsnolinks.html