Personally I wouldn't bother because >

I like the yellowed look, but can get it done here (not by Rolex) for peanuts and just a few days wait: I once had a whole 18039 done and it came out mint.

I have no idea how to go about doing it with Rolex as i've never used them for anything.

As for prices, well,,,,,, I personally wouldn't touch a concealed bracelet with a barge pole in white or yellow as they don't have the vintage look I want from one of these. You can (if it's really nice) make an exception for rose or pink as these did not follow on into the sapphire models until a couple of decades later: This is just my own thinking/standard of course and there are those who will accept and like things that I will not.

As for prices, white foldy clasp bracelets are so extremely very difficult to find and are worth as much as the individual collector is prepared to pay on the day. For that reason I am afraid I cannot share my opinion on value as I am still searching for another 3 and obviously do not want to screw myself to the world by letting them know what I would pay.

If you're not an insane purist, my advice is buy a nice single quick and full 18039. You can get a real nice spanker for $12K and you wont have to do all the messing around, hunting and heartache that goes with bloody plastic models and the parts finding that goes with it.

hope this helps,

Steve