The basic way Re-casting works is if 'Item A' (be it a blaster or helmet or whatever) is that produced by a person/artist/company who has a current licence, or is a current manufacturer of said product. Now if a person purchases that product and makes a copy/copies to distribute themselves, without permission from the original artist/person/company, then that is Re-casting.. Also re-casting can be also labelled to someone who has made a copy of the original without altering it in any way, permission or not.
However, if the Original Artist/Person/Company loses the licence to make that product, or announces that the product will not be made anymore and is unavailable in stock permanantly, then that opens up a loophole into a Grey Area between Re-Casting and Not Re-casting...
The issue of Casting off of MR items have come up a few times, and im sure that it will many more.... Personally they have publically announced that no more Star Wars items will be made... so in all fairness if a fan or someone takes up the mantle to create these items at very near to, if not, cost price then I wouldnt consider that as Re-casting, nor slap that label on them...
Thats my 2 cents...