Hmmm... I have an equally elderly Winchester 69a that I was thinking about using. Mine is the detachable magazine model, where yours is the tube feed, IIRC. Yes, they do shoot nicely. You could check with Gunpartscorp.com; they might have one of the Model 69 (or 75) target-model stocks. It could be whittled down to a nice sporter stock.
I might also dust off my old Win320. It's a real oddball - an Aussie-built rimfire that Winchester sold in the '70s. Turns out the guy who designed it is the same guy who later started the original Kimber of Oregon. My "Proto-Kimber" shares some parts with the original Kimber 82. Guess I'll see which one like the 100-yd. target better. As for centerfire, I'm still pondering which to use.
Thanks for the source on the stock. The stock on this one was cut down to about a 12.5-13" length of pull when I was a kid (had the extra piece too, just saw it in the 80s). But it's in good shape and my recollection is it shot pretty well, so it might be fun to try. Probably better that my light barrel 10/22 with those *hitty sights. I'm looking forward to it.
Interesting, this may be the only rimfire in the shoot that is not a .22. Do you still have or can you find find ammo for it?
I'm glad to see that the USPS "Priority mail" is holding true to their claim of 2-3 day delivery, at least for some of you.