Yes SevenSepents. The later 7-round 45 mags work fine in the early 4513TSW guns. They just stick out of the magwell a little.
There was a fellow here that was going to try to manufacture a sleeve so we could use the 7-rounders regularly..........but that project never took off. Evidently.
When I was working and carrying my original 6-round 4513TSW in plainclothes, I would carry a 7 or 8 round mag on my belt as a reload. Just be careful not to get too enthusiastic when putting the longer mags in the gun.
You dont want to bend or break anything! Regards 18DAI