Promotional pens come in just about any form you can imagine. If you can think it, there's probably a pen like it. You can certainly find a pen that's appropriate for your needs. You've got choices as far as executive pens that are usually given away as gifts or thank you tokens. You can chose a cheaper, more conventional pen to giveaway at trade shows, or all your customers.
Custom pens also come in a wide range of prices. They go from very cheap to very expensive. You can certainly find a custom pen, that fits into your budget.