Jim I'd be happy to build you anything you like. I can't compete with China made stuff price wise. Well I could... But I could only charge about $2/hr for labor
PM me with the approx size you want and I'll work up and estimate. Do you have mounting rails on your roof already? The biggest issue with a roof rack is keeping it small and lightweight because there is very little structure in a 4runner roof... or most roofs for that matter.