My advice is that you should be understanding. Being out of work is very difficult for many of us... it feels like an attack on your dignity. It would be difficult for me to be in a position where I felt I was relying on my girlfriends money. I am not saying that this feeling is rational. But, it is understandable.
I hope that you can talk about this with him without saying "I hate this male pride thing!" (not a good thing to say to him by the way). I would appreciate my girlfriend saying something like "I understand that this is a difficult time, but I really want to take this trip with you... please let me find a way to help." If my girlfriend said this, I would probably agree. Another option is to make this a loan... an idea that will be easier if he knows how important this trip is to you.
Be understanding and communicate. You shouldn't force him to give up his "male pride" ... you should instead talk to him about what you want and work out a solution that both of you feel happy about.