Wait for their frequent 60% off Sales on Custom Framing. They usually have them about every 4 or 5 weeks and it is well worth the wait. (If you sign up for their e-news letters they send the coupons to you by e-mail in advance of the newspaper adds.) Triple matting, preservation mounting, uv "masterpiece" glass and the custom frame I picked cost me $400.00 for the last one. The Antiqued frame was the big expense. Originally the cost was about 2/3 the price when I started framing the first print when it first came out. But sadly inflation (pre-recession), and then the cost on the frame had almost doubled by the time the Osgiliath print was published but I wanted to keep them all uniform so I sucked it up and paid the price. You could go with a very nice yet much cheaper frame and still do the triple matting for less than $300 per print pretty easily I would think.
Good luck.