It's locational. Some Wal Marts aren't being hit by the shortage. For me, all Wal Marts in the mid-Missouri area are wholly out of CoD. If Hal is in an area similar to this they may be stuck in the situation I described.
There's no "can't wait" in this scenario. It's going to be a case where, and I would put money on this, you won't see CoD Heroes S4 and S5 in retail period. So you'll likely wait forever. Standard Heroes Series 5 has been barely seen in retail but not at many spots. Unless you're at one of those spots, likely the next Heroes series you'll see in retail is Series 6.