100-325 USD
Your question answers itself.
100-235 USD
Depends on condition, etc.. Range 200-400
Need to know the finish and overall condition.
For age check the Remington Society of America here: (should be early 1960's) http://remingtonsociety.com/rsa/questions/barrelcodes
400
$250-$500.
$250-$500.
That really depends on the condition. Take it to a gunsmith or appraiser or go to auctionarms.com to get an idea of what they are selling for.
An autoloading centerfire rifle made from 1960-1980
No, there were many automatic transmissions in the 1960's.
The Remington Model 742 was made from 1960 until 1980, and it was replaced by the Model 7400 in 1981.