Importing orchids?

[PNGPhil]

I live in Papua New Guinea and my main experience with orchids is mounting and growing on local orchids that folk here sell at market (mainly dendrobiums and diplocaulobiums, as in my gallery).

I'd love to be able to grow some more 'exotic' blooms here - the climate should work - eg. cymbidiums, oncidiums or phalaenopsis. However, to do this I'd need to import them, and that starts getting difficult.

I don't expect anyone has any experience importing to PNG - but if you do, please let me know!

Alternatively, a friend at the National Agricultural Research Institute says you can only ever import anything into the country that is in the form of 'tissue culture', but I don't know what this means.

Could I buy orchids as tissue culture to import? And if I did so, what would be needed to turn them into normal plants?

Thanks for any help!
Phil