I bought a 92 Chevy van about a month ago. It's doing the same thing, the infamous converter shudder. Get's real irritating. I'm going to change mine when I get around to it.
Anyway, you don't need anything special for a converter with a 305 or mild 350. A stock converter will work just fine. One advantage of a 700R4 is you can use a little looser converter and not waste much gas, since you have lockup.
If your plans are never to go over a mild came in the 350, keep it around 1800. Stall doesn't really do anything to raise performance, it just let's you use what you already have. With a bigger cam, you need the stall to raise the useful rpm range up higher. No use in having a cam that really starts coming on at 2500 and the converter stalling at 1600. They also really help with holding it at stop lights if you have to raise the idle up with big cams. One thing a converter will do is take away any traction you ever had.
On brands, stay as far as you can away from B&M. They are junk. I've heard good things about Contenental. But it's hard to beat a GM converter for applications like this too.