I contacted Bushmaster today and have not heard anything of as of yet. My dealer is looking into his price.
555R, you are correct. As long as the mag is blocked to 15 rounds it is legal in NJ, but that may change soon. There was a provision made in NJ State law to only allow permanently blocked mags to 10 rounds, which the courts ruled against, but this too can be reversed. So it can go either way. But here's the BS. Legally we, meaning NJ residents, can not have 20 round mag shipped directly to ourselves. I asked a postal inspector about receiving 20 round mags and he said if the state does not allow the possesion if this item, it will be considered contriband. Plus, if the post office ships them to you, that is another offense. All alterations have to be done by the dealer or manufacturer.
In actually buying good condition 20 round mags costs about $20 and new $25. If I can only have 15 rounds per mag as state law dictates, I would prefer to get (2) new 10 round mags versus 1 new 20 round mag and have to block the damn thing. It's much more cost effective to buy the 10 round mags and also gives you a greater peace of mind.