Generally speaking there are three basic kinds of face-readable spacesuit helmet designs.
1. There's the "bubble" helmet like the Apollo suits had, with variations like the helmets in Alien.
I do love the clunkiness of this particular suit design but I expect it's rather expensive because the Lexan dome is going to cost more than our budget.
2. The second main kind of design I do not like because it's very visually distorting and makes it hard to read the faces of the actors. I'll call this the "Firefly" design.
The big cost issue is the visor itself. I haven't been able to source reasonably-priced bubbles. Flat pieces are likely to be the cost-effective way to go.
The other big issue is the method by which the helmet will actually attach to the body. Typically a pair of rings are used (like in the Apollo design). Another way to go is to make the helmet attached to the carapace which would then have the suit itself pulled up over the carapace -- similar to the way dive suits sometimes are made.
We're very price-conscious. When we say the budget for all three is $500 it really is $500 for all three of them complete. ;-)
So those are our thoughts regarding spacesuit helmets right now.