Ah ha, something I can actually help with----------
Having just bought a Sedona (Pick up on Saturday) I also thought that the side steps would look pretty good.
The place I found some was
Formula4 The No.1 for 4x4 Accessories, 4x4 Tyres, 4x4 Wheels and Van Accessories. | Home
I think they are about £190.
I have used this company on several occasions and they supplied side steps for my old Maverick many years ago, which still look smart now.
Cheers
Mark