Depends if you're buying as a shooter or collector, and what you're asking it to do as a shooter. Non-matching isn't necessarily a guarantee of poor performance, though I agree that all else being equal, all-matching is better.
Overall condition is just as important as matching numbers, and ultimately all the bullet is going to see is the bore.
I've never seen a Lee-Enfield that cheap. Maybe I just live in the wrong place. Is this a No.1 MkIII or a MkIII* (with or without windage and/or magazine cutoff)? What is the year? Where was it made? All these things can have a bearing.