That is a tough question actually. Depending on the type of cuts were made in the action, you may be able to. One thing Savage does to keep costs down is continue to run the production line during changeovers, so I'm told. You can end up with a very nice finish on a Stevens if the production run was full when they were making Model 14's, they simply threw those leftover barrelled actions in with the Stevens production run. Same thing for DM systems, you may have both type of cuts in your action for a box mag AND a DM, it depends on the run. I have a stainless action with both types of cuts.
The Stevens in 22-250 I just bought has the new center feed mag and no DM cuts, it easily could have had the old style DM cuts and/or the old stlye mag box cuts and/or the new centerfeed cuts . There are also corresponding action screw spacing differences, the new short action mag system spacing is 4.40" which is 1/8" further apart than the older mag systems. The LA spacing remains the same for any LA made.
Can you post a pic of your mag box opening?
Cheers