Yes.
$300-550, depending on exact model and condition.
Depends on what the rifle is, and whether or not you can trace it to the actual manufacturer. Interarms was an importer and distributor - not a manufacturer.
Over 3000 yds
Interarms did not make it. Probably chinese
It was early, but not the first.
100-200 or so
Depends on the quality of the stock and bluing on the steel. A standard Mark X in .30-06 in good condition (some use and wear, but nothing bad) should fetch $350-450 on the online gun auctions in my experience. There are some variations like the Whitworth which have a higher value (it will be stamped "Whitworth" on the receiver). Also, specialty stocks like a full-length Mannlicher stock will make it worth more as will rifles in the larger magnum calibers.
although the interarms is a good rifle. the value is not very high (don't know why) I sold one about 8 years ago for $300 and it was like new..................
Check old gun catalogs
Old gun catalogs
About $150