You won't get a new one, Even dealers are reconditioned,
These cars are quite sensitive to cheap sensors of any kind. Do a google search, or even a search on here and you will see many, many people have tried cheap MAF's and rarely do they report back of them working.
The dealers may not be cheap but they do work. Fitted 3 ECP mafs to a mates AUM golf, All 3 went within 2 months.
Fitted a dealer MAF and never had a problem since,
Out of interest what codes are you getting?