Assuming the following:
-Thureon Defense (and AEI) DO market the TD 45SA Pistol in Canada with TD45SAP 10rnd 45ACP steel pistol mags. Consider these mags available in the high $40 range.
-TD 45GA will accept Glock 45ACP mags.
-The GA rifle costs ~$50 more than the SA.
-The SA includes a 5/30 (5/25?) SMG mag, and more are available, also high $40 range.