I freelance as both a Japanese translator and programmer. You can see some translation pieces on my profile.
I'm not completely clear on what you mean by 'editing' here, but I'm assuming you want a Japanese-to-English translation and the final result editing down to around 2000 words.
As for a rate, the basis I would use for this job would be USD0.15 per English word, which would come to 300USD, so trim that to fit into your budget: 250USD.
I am online if you would like to discuss it with me.