Our gas generators are generally used for laboratory analysis, however assuming our generators can fit the demands, then it is possible they could be suitable.
As I mentioned, we don't have much experience with cryogenics, so any information you could provide regarding flows and pressures would help us advise you. If you already have the chamber, then the installation guide or user manual should detail the exact requirements.
I would also ask that you check that it's not liquid nitrogen that you require. As I'm sure you already know, cryogenics for any application uses extremely low temperatures for their effect. Liquid nitrogen is normally used, as nitrogen gas will be closer to the ambient temperature.