http://www.ebay.com/itm/7-8-22mm-Lef...-/291088629795
From the description:
Package includes: 1 x LEFT Hydraulic Brake Master Cylinder
Bore / Piston Size: 17mm
Wrong side plus the piston is too large. The 250's is 13mm.
Also, I won't trust my life to cheap no-name master cylinders.