Great watch and I think one that Heuer is quite proud of - they have one in their museum and you can take a look too at the Virtual Museum:

http://www.tagheuer.com/the-brand/history/virtual-museum-ww2/index.lbl

I'm not up to speed on the Solunar really, but you can glean some info on it there - first made in 1949, first watch with a tide indicator and an initial run of 1000 made. That doesn't really say how many were made in total but it's higly unusual to have any idea of Heuer production numbers at all!

As to value, I certainly haven't seen enough of these to make any sort of guess, not something you might see in a year of eBay watching. But definitely a very nice gift to have given to you at 12.

Some pictures of it would be really nice, if you can share.