First of all - please don't double-post. The Edit function exists for a reason, there's no need for you to constantly double-post, and you're skirting the rules when you do so.
Secondly: from a business standpoint, are you sure it's wise to be offering up sales for products that aren't yet completed and don't have any images to go with them? Bear in mind that I'm not trying to discourage you here, but some images of completed, saleable work might go a long way to encouraging customers. Putting up renders from the game and saying 'I'll be selling these' probably won't get you many customers.
As for your actual request: try researching through the 405th, there are dozens of current threads active that discuss mould making. However, consider looking on eBay for cheap mould-making supplies, there are literally hundreds of options that you could use if you're trying to mass-fabricate props on a shoestring - but be aware that you get what you pay for, so expect to pay a little more if you want decent-quality products.