Hi.
My guess is that it's probably real, after a fashion.
There's the Stradivarius instruments that the man himself or his apprentices made, those are rare and valuable. Keep Your fingers crossed

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Then there's the model Stradivarius that's been manufactured by god knows how many luthiers and factories, and those are not that valuable, but can be good or exellent instruments. Even I had one once and might still, haven't seen that box in ages. That was not a good one, not even for a beginner.
The violin pro is the way to go IMO, they can tell the real value and most probably know a potential buyer also, no matter what's the value.
Regards
Sam