Shh Typo, we don't want everyone to know!
You're right Krey, for some reason I was forgetting its 68 full-colour pages! My own experience with self-publishing should've waved it's hand up in my mind before I typed. With that in mind it's a decent price for self-publishing. Is it worth doing the maths and seeing how much cheaper a black & white version would cost? There's no reason why your strip wouldn't work in b&w - It works fine for many comic strip collections (Garfield springs to mind... and anything japanese is usually designed for b&w printing), and the cover would still be glorious colour.
Just tried Lulu.com, and a black & white A5 perfect-bound paperback of 68 pages would cost £2.18 to produce, compared to £9.52 for colour. Plus your profit margin.