Replacing just the vacuum pump in the G1322A or G1379A is not a good idea. The tubing and perhaps other components may be damaged and replacing the pump alone may cause contamination or damage to it over time (resulting in a short life time). Often the vacuum valve is damaged too, since it is positioned in front of the vac pump and catches all of the debris and contamination inside the vacuum system. The Vac Tubing should be replaced every 5 years. BTW: "Parafilm" is not a solution, nor is cheap auto store vacuum tubing which is not chemically or vacuum rated for this application. The vac pumps are only designed to last ~ 5 or 6 years at best (these are normal maintenance items). Also, yes Agilent discontinued the original vac pump for this model, but has replaced it with a cheap quality vac pump that does not work as well. The original G1322-60000 pump is better (and you can still buy them, see link below). However, before replacing the pump, the real cause should be found, otherwise the usually contaminated system will contaminate and damage the replacement pump and you will be back where you started, but with less money.
For future reference, next time you have a problem with any HPLC degasser module, start at this link:
http://www.chiralizer.com/hplc-degasser-repair.htmlThey have all of the correct factory parts to repair these systems with (at prices much lower than the factory charges) and perhaps more importantly, they can actually repair individual chambers, control modules, vacuum circuits and your whole degasser (any brand) for far less money than others.