The electroless nickel finish IS the H&R model 258. The blued versions are the earlier model 058 and later 158. They are from the 70's & early 80's, before NEF's time. The stocks are original, there are some recent models from NEF that have the straight stocks, some are special commemorative models, like for the NWTF. I don't know if any current models are offered with that stock style, you'll have to look at NEF's site.
If you read my post, "What is the 357 magnum good for other than plinking?", you'll see that I regarded this as a rare find.......you may see a setup like this for sale tomorrow, or you may never see it again......!