Your Air pistol should have a serial # XXXXX B101067 and B111600
Since you have the original box etc, it may be worth something to a collector. There are air pistols on eBay for $3 upto $50. As for fixing it, I think a new air pistol would cost less than a repair of the old one. But, if it has sentimental value, it may be worth it. Let me know and I will try to find where you can send it.
Hope this helps...