Hi stusha,
I got oat cereal from Co-op the brand is Baby Royale and it's organic Oat Porridge, says the age is 4months+. It cost about 13dhs for 125g.
I also saw oat cereal of the brand Organix in Spinneys, I think that was a bit more expensive.
twin_butterfly thanks for the tip!
The Organic Shop has them in the cereal and grains section.
If you go on the 3rd Saturday of the month, they give 20% discount on everything in the shop.