I'll throw in two more cents worth. I'm also of the opinion that the SKS isn't much of a rifle in it's stock form. But modified I think it's fine rifle. It fits me a lot better than any AK I've used, but nowhere near as good as an AR.
I'm a big fan of the Tech Sight and spend the extra five buck for the target front post. Not very good in very low light though. It's definitely a problem at night. The Tech Sight is likely to require you to do some basic dremel work to get it to fit with a T6 stock. No big deal.
I'm attaching some photos that may help if you haven't seen the items in real life.
There is a receiver cover mount that does work, but it's expensive. It's from DC Engineering. I've used a number of their items over the past seven or so years and I'd say that this is the only part they make that is worth buying, and it is excellent.
If you look at the photo you'll see that it "grips" the sides of the receiver and more importantly it has set screws at the back of the mount and tightening them down locks the system. Since apparently no two SKS's are made the same, the amount you have to tighten the screws is variable according to your rifle.
You'll also notice that using this mount, just like a Tech Sight, you need to replace the latch pin with a bolt and nut. On the bright side though, using a bolt for the receiver cover really makes a difference on how secure you can make the cover.
You have to call DC direct to order this item- you must be certain that you're getting the version that has the set screws. Some versions do not, and that's just wasting your money. I've only used it with RDO's, a very short scope would probably be ok but I'd be concerned with ejecting brass hitting the scope and breaking it. A scope and an SKS don't really seem to go together anyway.
http://www.rifletech.net/cgi-bin/shop.pl/page=sks4.html
Just for kicks, if you want to go further and spend even more, the third photo is the PWS FSC-47 compensator. You need to get your muzzle threaded, which is not a big deal. It's pricey but dang nice. It doesn't seem as effective as the FSC-556, but I think that's just a matter of the SKS bolt assembly's mass moving the rifle around and not a problem with the compensator doing it's job.
Playing the 922r game sucks, but I always play it. If you need 922r parts and want to get the trigger worked on, I would send it off to Ben Murray now. I think Kivaari does great work, but the trigger, hammer and sear that Murray now makes and sells are really nice, and it makes better financial sense to have Murray do all the trigger work. That's three additional compliance parts and a much nicer trigger - an option we didn't have even just a year or so ago.
On the other hand, unless Murray has upgraded the spring loaded firing pin, I recommend staying away from that. In my experience the springs eat themselves in short order and leave a mess in the firing pin channel. It seems like a solution in search of a problem. Just keep the pin channel reasonably clean and you're good to go. Not a compliance part either.
Be aware that Tapco plays games with it's compliance parts count. The T6 stock is only two parts, not the three they claim. You must REPLACE a part to have it count for 922r. So ADDING a pistol grip does NOT count towards 922r.
I recall that Tapco claims the op rod as a compliance part, but also IIRC, BATF doesn't list the SKS as even having an op rod, so it obviously can't be replaced.
The Tapco 20 round mags are very decent. They've always worked very well for me. However you do need to pay attention to the instructions regarding magwell width. If you use those mags in a T6 stock it's a non-issue, but if you use them in a standard wood stock, then magwell issues can show up and that affects how well the mag will feed.
My feeling is that the only downside to the Tapco 20's is that the feed lips should be beefier. They don't actually break, but they do get weak, when that happens rounds can move out of position or pop out pretty easy. Not while in the rifle, but if you carry them in pouches the top round can easily move out of position and screw up your reload. Does count as at least two compliance parts, and maybe three, so that's a very good thing. I've always counted them as two parts, just to be on the safe side.
BTW, the rifle in the photos is a D version, so it actually does use AK mags.
Good luck and have fun.