I'm going to address something before I answer your question. There's no where on the guidebook that states that one has to be a mod/admin to answer a question. If the answer is not what you are looking for, please kindly say so, and then either PM one of us, or wait for us to get to the question.
Now, onto your answer.
Gigai's are Urahara's special invention. Not every Shinigami has one, and they only have one if they are trying to blend in with the real world people for long periods of time. If you are just visiting the real world, you do not get one. If you are going in for a prolonged mission then it is up to who ever plays Urahara (If we have one at the time) if he will give you one. If he's not being played at the time, then the Admins/Mods will decided what to do at that time.
Does that answer your question Kohana?