If the forks aren't to your liking, and aren't correct, maybe you could find an OEM set from a forum member near you for cheap and start over? Otherwise, get a set of "straight-rate" RaceTechs (or other brand) if you are looking for a performance and handling increase, they are pretty affordable. If you are looking for a for cushioned ride just for cruising, get some progressives.
Murphs sells a kit for about $25 to change the shock fluid, but I do believe you are over the pond. Go to your local bike shop or order online some shock fluid - NOT fork oil. They are not the same thing. The shock holds about a perfect 8oz after it is drained. Warming the shock up helps it drain out. A small baster of some sort makes it easier to get the fluid back in. You can't really "pour" it in, it has to be injected. Also, if you have never taken the shock off before, be very careful with the black plastic 1" adjuster - they are prone to break or fall off later after a reinstall. I would suggest when reinstalling it, put a little RTV (or lock-tite) on it so it is glued to the treaded rod.
BTW, I'm 200lbs and run 5" cut stock springs with a PVC spacer up front with Belray 15w oil and 15w fluid in the rear shock set on "2".