I have a GS500 swingarm with an adjustable gixxer shock and caliper you can have for 30 bucks.

I also have a Bandit rear wheel (4" wide vs. your 3.5" wide GS wheel) you can have for $100. I had a custom aluminum spacer machined to put the Bandit wheel on my GS (allows you to fit up to a 160 rear tire...though I'd recommend sticking with a 150). I can probably dig up the spacer and give it to you with the wheel. I also have a gixxer brake arm to go with it that will clear the wider tire (stock one won't). The wheel comes with a rotor and bearings too. I have some other GS stuff if you're looking.