833 rebuild

Okay, @hemidart69, I have a couple of questions for you.

First; Are you a decent mechanic? @mcodecuda and @Oldmanmopar and @69hemibeep are right. The 833 IS an easy rebuild. About 20 years ago, I converted my 69 Barracuda from an automatic to a 4 speed with parts from a 69 Barracuda Parts car. The transmission made a grinding noise going into third, so I pulled it and thought I'd try the rebuild myself. Using an article on 833 rebuild from an old Mopar Muscle Magazine and the Factory Repair manual, I tore into it. I bought a rebuild kit from Brewers. You can get them cheaper elsewhere, but they are good people. I took lots of pictures throughout (they came in handy later even with the two reference manuals). I did take one of the shafts to Topeka Transmission (best transmission shop in the area) to have them press off the bearings and press the new ones on. It worked fine after the rebuild. If you are a decent mechanic, you can certainly rebuild it yourself.

Second, since you are building a 69 Dart with a 528 Hemi, I assume you can afford to have the transmission rebuilt. That means you need to find a place to have it done. A specialty shop like Brewers is awesome, because that is all they do. However, any competent (emphasis on competent) transmission guy who has experience with 4 speed rebuilding can do it. When I took the shaft to Topeka Transmission, they told me they had a few guys who could do it and quoted me a reasonable price with a quick turnaround. You could probably find a similar transmission shop in your area. 833s are easy to rebuild, so like I said, any competent person with manual transmission experience can do it.
Good luck with whichever route you take.