I ran a Hughes 11" 3000 stall for a while with a 440, 3.91 gears in a '67 Dart and eddy heads and headers, with a 245 @ .050 cam and then a 248/254 @ .050 cam. With the second cam, I got boost from going to a 3800 stall 10" converter. But it ran very well with the Hughes with the smaller cam. the Hughes uses a stock flexplate and 5/16" bolts. My new converter uses 7/16" bolts and I went with a B&M flexplate.

If you see more engine upgrades or a bigger cam in your future, you might want to get a 10" 3500 stall now. Otherwise a 3000 stall 10 or 11" should work well with your combo. With a good converter (or maybe it's modern methods that many are using which minimize heat/slippage with street driving), you wont notice a huge difference when you're just doing normal driving until you hammer it.

Hughes was about the cheapest known brand when I was originally shopping. I now have an Edge converter which I really like. Not much more slip than the Hughes in normal driving, but when you get on it, it flashes up around 3800 and you're on your way.

You might hit ebay and the classifieds here to see what people are getting rid of. The edge converter I got is about 650 new, I got it for 380 shipped (shipping is around $50 when I sold my old hughes for $250).