I do think Thule could be your best solution, but if it's a one time thing, you can perhaps check out Amazon and get some universal (adjustable) roof cross bars.
Something of that sort:
Hcosmy Car Roof Rack Cross Bars,52” Thick Aluminum Crossbars with Locks Universal Roof Rack Adjustable Roof Cross Bars,Fit Raised Side Rail with Gap,for SUVs, Sedans, and Vans Pack of 2: Buy Online at Best Price in UAE - Amazon.ae
Then on top you install a weatherproof storage bag:
Rightline Gear Ace Jr Weatherproof Rooftop Cargo Carrier for Top of Vehicle, Attaches With or Without Roof Rack, 10 Cubic Feet, Black: Buy Online at Best Price in UAE - Amazon.ae