I'm not convinced you'll get these behind any of the Volvo factory 17" wheels.
I think that if you can find 159 calipers at a reasonable price, its a pretty decent caliper and even nicer being that it is radial mount. Seemingly, they're $400 - $700 a pair as a bit of a rule of thumb.
The holy grail of 'cool' here is going to be one of the oem/genuine Volvo AP Racing brake package, available as an option when the cars where new, which is long since NLA.
Renault Megane RS radial mount Brembo calipers are a good potential option here too and seem to, typically, be cheaper.
The Porsche 'big red' caliper upgrade, using 330mm S60R front rotors can be made to fit under 17" wheels, though some wheels may require small spacers to clear. Being Porsche calipers though, they do (at least in Australia) demand a premium price. This would probably be my pick of the bunch in terms of multi-piston calipers in the non-aftermarket space - who wouldnt agree that a porsche logo peeking out from behind a wheel spoke looks really cool.
Depending on your application, of course, we do a 320mm front brake upgrade package for the P80 platform that uses calipers from LS-LV Focus XR5 and Volvo S40/V50 T5 AWD models - it uses just about everything as off-the-shelf parts and is entirely 'bolt on'.
While its a vast improvement over either of the standard 280mm or 302mm factory brake packages, it still isnt a multi-piston caliper. With a good set of pads, it's more than capable to serve you well for track days and even light motorsport events.
Via another of our partners, we'll have a true multi-piston brake upgrade available soon, in a few different configurations. We'll fit that up to our V70 soon(ish) and do some wheel test fitting as well to see what factory wheels we might be able to get on the car.
