I think the all red contact lenses may be suitable for the halloween holiday. It is so personal and unique. You may go to the near eyeglasses store to have a search. And I think buying online will save a lot of money for you. You could go to the big online stores to have a look and see whether there is such type, like the walmart where owns a lot of contact lenses.
Well, don't you think that it will make you look like a demon or somehting evil?
However, if you insist on wearing what you care for, it does not matter. Personally speaking, it depends on your personal taste. As to where to buy, maybe you would like to visit MaxMart vision center and Best Buy, you can easily find lot of different types of contacts at low prices. Hope you can get what you want.