I like the 500 series bolt guns. I have two 511s, 1 512P (gave my son-in-law a 512 3 months ago), a 521T that I sporterized & finally was able to find this 510 @ a decent price. It is no "cream puff", but it's all there. According to the bbl. stamp production date was 3/48. The stock is split on the left side, but no missing pieces. The metal is slightly past patina & headed toward rust: but the bore is good.
The stock can be repaired well enough for use, but appearance wise will not be perfect. I plan to restore it for a 1 yr. old great grandson. I'll shorten the damaged stock & I've ordered another stock from Gunville (www.gunville.com) that will be full size that he'll be able to use long after I'm gone. I may get up enough nerve to D&T for a receiver sight: I have one from Havlin Sales. The Mossberg bolt guns have the same receiver diameter as the Remington 500 series.
Here are some photos.