4 Speed w/ Overdrive Any Good?

I have had one behind an ~ 370 HP 360 for 45,000 miles now with no issues. I drive the car hard and have been to the strip a few times. The gear spacing is not ideal for maximum performance but its not an issue with a street driven car. I have run a best of 13.7 @ 102 mph with a very traction limited 2.2 60' time, there is a lot more in it (at least low 13's) if I was ever to sort out the traction issues.

Your current shifter will work. The bearing retainer on the front of the A833OD is 5.125" in diameter. Your car likely has a 4.805" bearing retainer (could be 4.3xx"), if it does and the tranny has the larger 308 front bearing the retainer will swap right onto the A833OD. If it doesn't you can buy the retainer from Brewers or have the one you have turned downed (note if you have the 4.3" retainer you won't be able to swap retainers or machine it to fit the bell and you will wind up needing to get the bell machined.

$650 is way to much unless the seller can provide proof of a rebuild. You can also use the long tail shaft version that came in light duty pickups and vans, those you can pick up for around $100. You will need to shorten the drive shaft and fabricate an adapter plate the mounts to rear mount on the tranny and positions the shifter forward to the A-body position, bigblockdart.com has a drawing. I have one of these in my 68 Barracuda.