You'll have a hard time finding an SL or FE for that kind of money (most are at least £1k more than that) but you'll probably find a decent (not mint) standard SS for that.
The only differences really are the single seat unit and high-level pipes but both can be found aftermarket. The reason SL/FEs go for more is that they have generally been better looked after as well as the rarity value.
They are not more maintenance hungry than a jap bike but respond well to a bit of patience with the setup.
The engines are pretty much the same as monsters of the same era but they tend to have lower mileage (tend to be fair-weather ridden rather than all year round like monsters) and should be very reliable. I don't know about the cylinder head bolts but wouldn't have thought they would have been changed.