Most Honda tanks have a very narrow tunnel, and don't fit the Savage frame very well. The same is true of most tanks that come from old dual sport (enduro) style bikes.
I have a really nice NOS GS450 tank if somebody wants to buy it. I bought it to use as on a "standard" style Savage conversion - but it is just a little bit long to allow the use of a double seat like they used on the bikes in the 60's and 70's....it would work fine with a single seat.
It has a few small paint chips, no dents, no rust.
$150 plus shipping.