You can get the handle anywhere you can buy the shifter(I know Texas Mustang Parts as them in stock). I'm getting a tri-ax handle for my pro 5.0 here soon so it'll be a little more comfy and closer to me. I love my pro 5.0 (and I really like the steeda knob!
Go Pro 5.0 ! Never missed a shift, but have accidentally left it in 3rd and tried to pull away from a dead stop - tried, but quickly figured it out and pulled it over into first, no biggie. With 3.73 or 4.10 you can leave a dead stop in 2nd, but I'd never knowingly try pulling away in 3rd - that's just stupid abuse - I'll park it first. 5th gear is a stretch on either the Pro 5.0 or the Tri-Ax, but seriously, how much fun is 5th gear anyway?!?! There is no way you'll ever miss 3rd and hit 5th...no way, never, ever, never.
Both the Pro 5.0 and Steeda are quality shifters. Can't go wrong with either one. BTW, the gear noise you may hear has a ton to do with what kind of knob you put on top. Put the OEM leather knob on and you'll hardly hear a thing. That's what I had for a couple months, then went with a 2.25" black fatknob - lots of good ol gear music now, but it doesn't bother me.