I got a pretty good deal on some 1" wheel spacers for my XL7 on eBay from Titan Wheel Accessories. You could give them a try. I can't give you any review on the spacers because I haven't put any miles on my vehicle since the install, but I can tell you I did not need to cut any studs.
I think you will find that the wider track will help you vehicle BE more stable, but it might not necessarily FEEL more stable, because with your soft factory springs, the fact that the wheels are farther out from the springs by an inch per side means that they have more leverage to act against those springs. This is a benefit off road because it helps coax some travel out of the IFS, but it's a disadvantage on-road because it will work against you for the same reason.
I think your misconception of suspension spacers adding to the spring rate may come from different vehicles with different IFS setups. I know in a previous truck of mine, a 2004 Tacoma which uses a coilover "strut" with upper and lower A-arms, ( versus our vehicles which use a separate coil and strut and only a lower A-arm), if you added a spacer inside the coilover assembly, it would stiffen the ride because it was basically preloading the spring, similar to what happens when you crank up torsion bars on an older IFS Toyota. However, there was also a style of spacer called an over-the-top spacer which didn't install inside the coilover (no need to disassemble the coilover), but just bolted between the coilover assembly and the frame mount for the coilover. This would give lift but no difference in spring rate because all it is doing is moving the spring mounting point lower relative to the rest of the chassis. This is exactly what the spring spacers in our Suzukis all do. All you are doing is moving the spring mounting point down. You could put a 9" spacer on there and it wouldn't be one iota stiffer than a stock setup. Check out Whitfield's rig on Zuwharrie if you don't believe me; he basically did just that, lowered everything down 9 inches.