Which radiator hose for 69 camaro bb?

[HRBS]

your radiator look to be a cross flow design (inlet and outlet on same side).
this is different from the factory design therefor a factory hose for you app will not work. We use exactly what you have there (flex hose) to make a template by bending it to the shape we need and then take it to the local NAPA where the manager knows us and lets us in the stock room to find a match. Thats your best bet IMO.
I would also suggest repositioning the swivel neck to be straight. Finding a hose with a perfect 'S' shape will be easier than finding one that is slightly bent.