Oh boy--I hate to tell you this--but it is rude to ask for money(or anything else) for gifts. A bridal shower is intended to help the bride be prepared for married life, not to buy her(and her groom) a vacation.
There is never any way to tactfully request specific gifts. People who care about her may want to purchase something for their shared home, and some really kind and thoughtful people may even want to make her something: a quilt, some artwork, something special that signifies this important stage of her life. I think you are going to have to go with tradition here and just throw a shower with no specific gift requests, or to say 'no gifts, please'. Sorry.