Platte I have a 641 Triple Range. This is a nice little tractor. Don't know how much you know about the 630 series but it is a short run line made from 1960 thru 1963 vs 1960 thru 1969 for the rest of the 30 series tractors. It is bit more collectable I think because of that it never made it to the Comfort King change and most were offered with eagle hitch only I believe, Lorne (ACG), Tom (Case Nutty) and John Saeli as well as Melvin (mEl) who is a long time Case mechanic can confirm that. These guys as well as many others on this forum are a wealth of info and help, at least they have been to me. John (http://saeliimplement.com/)is a good source for new and OEM parts and supplies. Others that monitor the forum are also good sources for salvage parts. If you are needing the pump just post a message out here and one of these folks will chime in. I have done business with most of them and they are all good honest folks.
Hope you get the tractor, its a nice machine.