£10 is far too cheap, you are effectively loosing money, at best drawing evens. The visible costs are easy to work out, but I did a calculation on the hidden costs, and that includes everything from bandsaw blades, all consumables etc, but I did not include depreciation, so just the costs of actually making the pen, and one cost that often gets overlooked, the cost of sale, the cost of the pen stands, the cost of the spare refills, the cost of the box, the cost of the coffee whilst at a show, it all adds up, in fact, with table fees it costs five quid to sell a pen before you've even costed in the cost of the kit, the wood, and the profit, if in deed you are really making a profit, or are you invisibly loosing money?
Don't go along with the variation in cost according to wear you live, sorry, but have sold streamlines successfully at shows from Scotland to Germany and all counties in England and Wales in between. Never been to Anglesey. Pen cost £15, always.