Mark, keltec does not make a 10 round magazine for this at the moment. I know it sounds weird but you are allowed to own magazines higher than 10 rounds in Maryland. You just can't purchase them in Maryland. So you could legally buy a 16 round magazine for this in Pennsylvania or Virginia and legally own/use it in Maryland. Again you just can't purchase/receive them in Maryland. So I'd contact some FFL dealers in PA or Virginia and ask if they have any magazines for this. I grew up in Maryland but luckily moved to PA. If you Google ( how to own high capacity magazines in Maryland ) it will show you all the ways to legally obtain high capacity magazines in Maryland. Hope this helps.

There are currently no 10rd magazines available from keltec, there is a company that sells a mag-block/ limiter, but buds won't ship the magazines to your state (they can't legally do so) if you could buy the magazines in a neighboring state and install the blocks yourself (in stock here magazineblocks.com/magento/kel-tec-p17-22-10-and-15-round-magblock.html) buds would ship you the pistol with the restricted magazines removed. But your best bet is going to be trying to find one at a local shop where the ffl can pin the magazines before the sale.