International wireless standards

Hello,

I may be doing some documentary-style filming in a year or so in Nigeria. Probably just a one-man crew - little or no budget. Much of what I'll be recording will be indoor interviews, so I am intending on getting lapel mics. I would like to get wireless mics though, because they give me more freedom to move, and if I want to move it outdoors, they will allow me to do that.

I need to know if there's any problems taking wireless mics certified for Australia overseas anywhere? Is is illegal? Just frowned upon? risky due to frequency interference? If not, I may invest also in a wireless, handheld mic for presenter-style interviews.

What do you think? I know its as far from ideal as anyone could get without just relying on the on-board mic, but I'm trying to do what i can!

Cheers!