I would think on a coin of this value, the cost to slab would be a good investment, even in a details grade, just to certify it as a genuine overdate.
If you'd waited for silver to come down to its current price, you might've been able to get it for $1.45. Don't you hate it when that happens?
Definitely a 1942/1 D. I've actually pulled two of these out of junk silver and another one off of ebay. If the mintmark isn't too worn down you should be able to see that it is a D/D, which is one of the markers for this coin. But, because of the rim dings I would call it VF details, still for a buck sixty you couldn't go wrong.