Heido, 

You can try to go to the Omani souq or the shops around it. Instead of the mesh you can buy this green (or other colors available too) material. There are some shops there too that sell poles. Also try some of the garden centres like Florenza. If after your trip you still have not found it you can send me a mail as I have a roll of mesh here, which is very old, and do not know if this is what you want.

Aisha-Taweela