"Euro" in this context is BMX terminology. Traditionally, BMX bikes used the old, large American standard bottom bracket with a threadless shell and one-piece forged "Ashtabula" crank:
Three-piece cranks (two arms and an axle) are more popular these days. There are several ways of mounting the axle bearings that correspond to different frame standards, and "Euro" just means standard BSC threaded cups as found in a normal MTB.
I don't know much about the BMX world, but there seem to be several different axle diameters in use (19mm and 22mm seem the most common). I don't know what your MRP cranks need, but CRC stock several other Euro bottom brackets:
http://www.chainreactioncycles.com/Sear ... om+bracket
You'll find even more at a BMX specialist.
Calmes dans le demi-jour
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De ce silence profond.