Chain/Front sprocket/rear sprocket
If you need new ones this is probably better kit than OEM (not that you need it o ring is fine), much cheaper, and you can collect from Broxburn to avoid postage and they'll quite happily change the rear sprocket they give you with the kit if you want to change the gearing (better acceleration, but makes motorways a bit buzzy)
http://cgi.ebay.co.uk/DID-X-RING-Cha...742.m153.l1262
Rear suspension
How much do you wanna spend and do you want something that just fits or requires some cutting to make it fit? Just 'cos I know you, I suspect you want new, so it goes from an Elka (best!) or Ohlins rear shock at 5-600 notes, down to Nitron Sport at 350 odd (good comprimise I believe), then down to a Hagon shock at 250 odd which I believe is not much better than the OEM. Hyperpro do a range of shocks with progressive springs too but no idea what they cost. None of this comes from experience, just from research and reading.
front fork oil
front fork springs
Hagon, Ohlins and Hyperpro all do fork kits for about the same money, so again, just from what I've read the smart money seems to go on Hyperpro progressive springs.
exhaust
If you only want it to sound better, I can't see the point of adding a few horsepower, it's not about power the SV is it! Wait and see what I do with my bike, I can't promise anything just now, but if things just happen to work out in such a way that I can't use my fuel can you can have it and either pull out the dent or stubby (if that happens don't tell OH, 'cos it was a pressie!)