AR Upper 5.7x28 or 5.45x39

[Pourv Lac Dionne 2008]

hello,
I search some information about this 2 upper
quality Cost Ammo and mag
and where i can buy one ?

it is easy to found 5.45x39 ammo here in Can

If you can help me just reply
Thank you

 

[gallen270]

its expensive, ammo is hard to find, but its got a cool factor.

 

[mrsmitty]

Questar sells the mags.

 

[alexD92]

5/50 round mags. Neutered like a liberals dog.

 

[Pourv Lac Dionne 2008]

other question

It is easy to found a upper in 5.45x39?
if i found one can i use my regular lower and mag?
thanks