Check out
www.weaver-mounts.com. They list their #46 base for use on the Stevens 200 for front and rear. They also list a #402 extension base.
A word of advice, if I may. Take the scope to be mounted with you and check for the ring position with the #46 base vs. the Objective and Ocular bells. I know of several folks, myself included, who had to use the #402 extension base at the rear. Its not a big deal. The mount just moves the rings inward on the tube. This will allow you to obtain forward to rear movement of the scope to adjust eye relief. The mount will hang a bit over the chamber opening. Again, not a big deal as it will not interfere with the bolt operation and cartridge ejection.
I have seen that it doesn't always make a difference if the rifle is a short or long action. What matters is the taper length of the Objective and Ocular lens bell's of the scope.