What is the value of 30-30 Winchester saddle ring carbine serial 348668 with a Marbles Tang sight in good condition?

A answer depends greatly upon what good condition means. To me, good condition means in its original configuration and un-touched with respect the the finish of the wood and metal. Normally, the bluing will be at lease partly deteriated, which is an indication of its original condition. If it has been re-blued, or the wood refinished, its value is much less. Also the bore and rifling need to be good, with no pitting or rust. With the said serial number, it would have been made in the early 1900's With this in mind, the rifle may bring $500 to $800 on one of the gun sale websites. JMG