Sharps,
Congrats on scoring a Wiselite. They are fine shooters and I enjoy mine very much. You can indeed use those cheaper Sten mags, but they are a bear to load. Plan on ordering one of the loading spoons that are available on the surplus market. You should be able to get a loading tool for $10 to $20 bucks.
There are two types of Sterling mags on the market. Those that are below $40 bucks each and will probably take refinishing. Finish doesn't equal function, but if they look too badly beaten up, keep looking at the gun shows or on line. Sooner or later, someone will have one or two and not know what they are really, so will have them at a decent price. If you assemble enough mags with no finish left, you could send them out for ceracoating. Just make sure they are good functioning mags before spending the money on them. Black is the right color.
Then there are the pristine Sterling mags that are going to be $75 or more. That seems outrageous, but considering the last of the reasonably priced ($35.00) Sterling mags were probably sold 5 years ago, that is just what happens. Keep your eyes peeled and learn the difference between the Dagenham "Magazine Sterling 9mm 34 rds" and the L1A2 government contract mag. (I know, get's confusing) Both excellent mags.
By the way, if you get a mag that seems to be giving you mis-feds, check for parallel feed lips. The lips do get bent and are fairly easy to bring back into position.
Included are a few pics to illustrate differences. You will even see my 20 round Sten mag, which works just fine. Enjoy. You got a great little rifle.
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