No matter what you put behind that big block, your requirement of both street and strip with a stick tranny are at odds. I race with a lot of big 5xx motored 8-9 second chevys with either 4 speed Jericos or Gforce 5 speeds and they holdup very well, mostly due to using racing slipper clutches. I would say that nearly all are strip only cars that use purpose built drag racing transmissions.
Liberty makes the strongest transmission, but I don't know if they make a dual purpose transmission that is 100% streetable. Not sure how the Gforce will fair out either but it isn't as strong as the Liberty. Most clutchless shifting transmissions will not be streetable. You can drive some of the other dog ring transmissions on the street, but they require special driving techinques which might get old on a 90% street car. Normally double clutching is needed and even then they might grind and/or clunk. I found that faceplated type gears are quieter and will last much longer than proshifted gears in the old toploader and will work fine when double clutching.
I an certainly not the expert at these transmissions and can only offer my opinion. Of all the commonly available racing type transmissions, I believe that the Jerico dr4-4 built with the road race sliders would best suit your requirements for a dual purpose stick transmission. Of course they are not cheap either, although they do come up on racing junk and can be gotten with shifter at times in the $2000-$2500 range. Here are some basic specs on these (there are infinite options and gear ratios available for a price):
You could buy 3 more new BB toploaders for the price of the one of those new and it might hold up just fine. For all my racing efforts, including the fresh proshifted liberty toploader that i toasted, my total transmission investment still hasn't come close to the cost of a new Liberty, Gforce, or Jerico. For my weekly assaults at the track I maintain 2 toploaders to ensure I don't miss a race date. One is liberty prepped and the other is sychro'ed. It takes me an hour and a half to swap them out. Rebuilding them gets into the 3 hour range. Most of the race transmissions mentioned above can be rebuilt in an hour or so. They are also lighter, with the jerico being in the 95lb range and the common gforce 4 speed being close to 80lbs.
For any of these transmissions to live, you will also be investing in a racing clutch. That is the secret to longevity. You may or may not like giving them attention too, which they require.
I can't believe I am going to say this, but for a dual purpose, carefree and easily driven BB like you are building a more sensible approach might be to build a C6 which will take everything that you can throw at it and still be both streetable and ready for the strip.