FYI, Oly does not manufacture the 45 mags, they rely on IMI for mags. Seriously doubt IMI is going to make more 16 round 45 mags.... but you never know. There should be a lot of 45 mags out there, as most of the Uzi SMG owners who have 45 kit are doing the spare lower with a MAC 10-45 magwell so they can rum M3 mag with 30 round of 45 instead of 16.
Might be interesting to see if the Hy-Tech block will function in the 45, but for sure the ejector will need remove from the block. The 45 mags are a snug fit to the std Uzi magwell, so the Hy-Tech block will require some filing to allow the 45 Uzi mag to sit and lock........ I'll have to see if I can install a 45 mag in mine, as I do have Uzi with 9mm, 40, 45acp kit, along with M3 lower for M3 mags.
EDIT- Your "OLY" dealer who lurks here is Mark, posts as 'budam',
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