Welcome to the world of 10/22! This is about the most expensive 22 you can ever have short of having one custom built for you! Think of it as a great 22 version of an AR-15, everything is modular, anyone can do the work to replace the parts (even you)!
The stock on the Kidd is actually made by McMillan and doesn't come cheap. It's a wonderful stock, and I wouldn't trade it for any other. No I won't sell it either! They are discontinued production, but
Rimfire Sports still has some in stock. Sadly they are not ambidextrous.
Boyd's does have a
lefty thumbhole if that's what you're looking for, they aren't nearly as expensive as that McMillan either! I'm happy with my Boyd's, even more than the McMillan considering the price.
Other places to look would be
Stocky's,
Brownell's, and
E Aurthur Brown. If you're really after an ambidextrous thumbhole you can find one there. Of course other retailers and specialty shops all have stocks too, but those 3 carry just about all the ones worth having. I do specify worth having, because you absolutely want to stay away from any clamshell stock design. I used to have the Red Jacket ZK-22 stock, and it was a 2 hour ordeal to disassemble, properly clean, and reassemble it. Cool factor sure, but practical not at all.
Although the best thing you can do to make a 10/22 more accurate is replace the barrel. The chamber on the Ruger factory barrels is a little too loose to accommodate any and every 22LR round out there. Aftermarket barrels are always reamed a little tighter than that, and more accurate to start with. I know both of mine were worlds better just replacing the barrel. If you watch just about everyone runs specials on barrels, but the best deal on 10/22 barrels I've found is in the 2 weeks before Christmas on
Green Mountain Barrels. No they're not as nice, expensive, or match grade as so many others, but there's not enough of a difference between them to justify paying the price difference. Green Mountain will usually mark down at least one of their 10/22 barrels 50% in those 2 weeks, and $80 including shipping is certainly much easier to stomach for a replacement barrel than 2-3x as much for TacSolutions, Kidd, or Volquartsen. Also I wouldn't bother to worry about changing the screws or V-block unless you're really worried about having over-torqued it and causing your own barrel droop.
The other upgrade I'd strongly suggest right away is to get rid of that bolt buffer (pin at top rear of receiver that keeps the bolt from falling out). You can use the nylon or plastic stuff, or put together something like
this one from KIDD. I love these things, especially when I screw the can to the end of the barrel. I can hear the hammer hit the firing pin after hearing the hammer click free of the trigger sear!
Yea the factory trigger isn't great, but it's technique not trigger design that's important here. I just got tired of such a heavy pull for plinking around a few hundred rounds at a time. I'm again a fan of KIDD, and their
drop-in trigger kit. It's not the cheapest way to go, nor is it the most expensive, but it feels great, breaks sharp and clean, and has adjustment for over-travel too. I got the tuning kit with different springs and have both of mine set around 2lbs. Volquartsen has a
similar kit but it's more expensive and is really a parts bag. Kidd's comes mostly assembled with good simple instructions (and link to how to video) to install.
The list of mods goes on forever, all sorts of polished parts, extractors with a sharper point, finer & harder firing pins to reduce light hits, different internals and trigger groups, and of course a seemingly endless amount of stocks! Spend as much or as little as you like, I've got more spent on both of those 10/22's than I like to admit. But they are mighty fine looking and very reliable tack drivers, doing so even with cheap ammo. Even my parents, who I've had to teach to shoot, can dot the Titlist i's on the golf balls I hang out there at 25 yards with either of these rifles.
Feel free to hit me up with any questions if you'd like, I'm always glad to help. Best of luck, and happy shooting!