a 22mm strap will fit on a 21mm 3717. its been discussed many times and answered by people who have done just that.
I just got my 22mm BP strap from Strapluxe and love it. you may want to consider them too.
www.strapluxe.com
lots of ap fans on this board including myself highly recommend getting AP ROO straps from StrapLuxe (www.strapluxe.com)
try them out. best quality for the price in my opinion
you can get leather straps for your Roo with Strapluxe or Oracle straps.
there is a thread just started today showing pictures of their straps on different Roos in the audemars piguet section. you may want to check them out
the Strapluxe gator straps looks like OEM! awesome choice for your rubber clad.
I never had a thing for fake carbon fiber straps (meaning they arent real cf but just a fabric cf pattern), but the fittment looks great on the oracle strap!
awesome mods.
makes me want to buy more strapluxe straps!
the Black croc strap I got from Strapluxe fits extremely snug against the oem endlinks. So euno, you will like the fittment of the strapluxe strap with your endlinks.
Do the HKTan's AP straps have a metal piece where the strap attaches to the watch casing like the OEM AP straps? I do not think so right?
I dont know if you want to put a flimsy strap that may break on such an expensive watch!