Been walking last week in Bond Street @ London. Stop by the lovely Salon of PP. Bought this fabulous matt brown strap for my 5104P (matching wonderful with the RG case sides and RG skeleton dial). Then keep walking to Gucci Boutique and found these awesome straps and couldn't resist them.
Especially with the red gold details it should work very well and even when it is hard to see on your pictures (the colour of the strap), I can imagine it very well.
The brand new Ref. 5304R should look great with a brown strap as well, because there is even more red gold.
Khalid, I can imagine you spent a great day - with lots of extratime for attention to details. Just perfect. Thanks for sharing!