What you got looks great to me. I'd call it a porter for sure. And I've made 'em with the English hops, too. I like Fuggles quite a bit.
I should have mentioned...when I'm trying to BS together a recipe on brew-day, we come up with what we want to brew style-wise and then fire up this piece of software called SUDS. It's been around forever, and it's a great piece of software. You can add malts, hops, whatever, and then see where your beer falls in the AHA guidleines as far as IBUs, color, gravity, etc. It's a *very* handy tool, and it really helps get the bitterness and color to a style-appropriate place. I have no idea how accurate it is in terms of gravity, as you might imagine
Par example...I ran your ingredients through SUDS, and got this. I assumed 4% alpha acid for the Cascade and 3.1% for the Fuggles. Note that I bumped the Chocolate down to 1 pound...that stuff makes beer dark fast. Also, this may have more finish hopping than some like in a porter, but I like a bit of finish hop in a porter myself. AHA ranges are in parentheses after your number as calculated by SUDS:
Random Porter Recipe
2 lbs Amber ME
4 lbs dark ME
1 lb Chocolate - steeped
2.5 oz Fuggles - 60 min
1 oz Cascade - 10 min
OG - 1.055 (1.050 - 1.065)
FG - 1.014 (1.012 - 1.016)
ABV - 5.3% (4.8 - 6)
IBUs - 29 (25 - 45)
Color (SRM) - 44.7 (30 - 50)
So, that falls right into style...
I LOVE that White Labs English Ale yeast. We have had incredible success with that one. With a good starter, it'll tear through 12 gallons in no time. If you rack a new batch onto a yeast bed from a primary, it seems to ferment in about 3 days. It's super-yeast. And it's not all weird yeasty/estery/British. It has just enough yeast character for my tastes when making British beers. One of our new faves for the light beer crowd is a Bitter that uses 2-row, flaked barley, fuggles and that White Labs yeast. Carbonate it with beer gas (NO2/CO2 blend) and pour it on the Guiness tap, and it's a lot of fun if you like that sort of thing. We have also made an Oatmeal Stout, IPA's and Pale's with that yeast. I can't wait to do another round of it.
Crystal malt comes in varying colors, as expressed in Lovebond rating. In general, it adds some degree of unfermentable sweetness and color. I don't use it in many beers because I usually don't like sweetness, but it was good in the porter. It's also called Caramel Malt. Your amber malt will serve the same purpose.
Your recipe looks a lot like mine, really, except you went British and I went American. It'll be a great beer