...it's a 2443 case, so that would be what I feel the watch is. It's similar to the better-known 2447 but with less case material surrounding the dial, emphasing the dial a bit more over the case than the 2447. To very good effect here, I might add, I particularly like the coppery seconds scale.

The 1946 catalogue has a 2443, again with written hours on the dial:

but interestingly the equivalent cased triple calendar 2543 (hence the difference of only one digit in the reference) is shown for the first time as using these brass studs as hour markers:

So I reckon this is a post-war 2443 that has received the same dial changes as that triple calendar, thus probably from somewhere between ~1947 and the start of the '50s. Note, I mean Heuer made the design changes to the dial, I'm not suggesting this was done post-sale! As a 13 ligne watch, I'd expect the movement to be a Vj 72 or perhaps 21, the Vj 71 shouldn't fit unless it's in the case directly without spacers. I have seen a few watches where a 14 ligne movement has been crammed in in just that fashion, so wouldn't rule it out.

As for restoration, yes there are people who could do that for you - we'd need to know where you are in order to suggest one. But I don't think it needs much doing - the "crystal" can be gently polished to remove the worst of the scratches and better show off the dial. The movement can be serviced to hopefully restore the chronograph to working order but that's as far as I'd recommend going - the dial looks gently patinated but that adds to its dignified beauty, I wouldn't let anyone near it to clean it up! That's all it would need to be wearable and a nice daily reminder of your father. It would have real financial value to go alongside that sentimental value - we see these less often than 2447s but I reckon the value would be in the same ballpark. I know some 2447s have been traded lately so some may be able to give a better idea of the value but it's definitely enough to make the servicing costs worthwhile.