I am selling my SL-68, for $40 shipped obo. It is in excellent condition and has only been used in one game.
However, it does need a new mainspring (no more than $5 from tippmann with shipping) as I clipped too many coils off the current one trying to get the velocity down on a hot day.
It does not come with the hopper or tank, but does come with the hopper adapter so it can use modern hoppers.
If you're interested email me firstname.lastname@example.org
or give me an IM on AIM at NuklirMachineGun