If they were sold as a "matched pair" to a Winchester collector there's no doubt that they would be worth more than two other Model 100's that are identical to them in condition and features, but which have non-consecutive numbers. But to find out how much more they'd be worth, you need to talk to several realWinchester collectors.

As far as I know, the Model 100's have very little collector interest. You'd be far better off with a matched pair of pre-64 Model 70's, or a matched pair of Colt single-action revolvers!

As for the significance of 1964 in the history of Winchester firearms, in 1964 the company decided to make every model they retained in the lineup as cheaply as possible. So everything made after 1964 has a lot of stamped parts,some parts in which plastic or aluminum replaced steel, and stamped or pressed checkering replacing cut checkering.....