Do you use the arrows, edit keys and F keys a lot? If so, then TKL is the right size for you. If you can live with the F keys, arrows and edit keys being on a Fn layer, then go for the 60% (Poker II), since it saves more desk space, allows the mouse to be closer to the typing area and looks way cooler

The Keycool 87 is a TKL that came in white with white caps, but it's hard to find the one with genuine Cherry MX Blues for sale now, they switched to using Kailh "clone" switches.
The Leopold FC700R is also a TKL that comes in white with Blue switches.
The Poker II comes in white, too.
You might like these doubleshot white on blue ABS caps from Taihao, but I'm not sure if the blue is exactly the one you want:

They will be available in the Taihao Group Buy when it reaches the next stage I think:
http://geekhack.org/index.php?topic=58110.0If you don't find the info you want in that thread you could PM GhostofHarry.
Other options would be more expensive, but there are some nice sets of blue / white caps out there. IMSTO sells some thick PBT blue caps like these for instance:
http://imsto.cn/index.php?route=product/product&path=62&product_id=61