I have a Durga 10 bari mouthpiece. But I like bigger tips than you do (I was playing a .120 metalite before this, and haven't gotten along with anything smaller than .115 on bari with a baffle for a long time). So I'd suggest the 8*. I did do a trial on an 8* and liked it very much, good power, I just wanted the bigger tip.
I recommend against the vintified finish. I've owned 2 tenor Durgas -- one vintified (size 8) and my current piece a gold 9. I also trialed a gold 8. In each case, I found the gold more attractive. It ages better (the vintified looks a little odd as it ages, in my experience). The mouth-feel of the gold is better. And I like the sound better -- Durgas are NOT super-bright pieces (Drake's contemporary crossover bari piece is MUCH brighter, for example, as are many Bergs). The Durgas have a nice thick clear sound. I have easily played my tenor Durga for straight-ahead jazz work with reed selection and practice (although I prefer my Gaia for jazz). The baritone Durga is more than versatile enough for everything from combo to r&b. You don't need to tone it down with the vintified finish.
No, don't get the extra pressure plates. I'm very happy with the couple that are provided. I've tried the others and -- although there's some difference -- its not worth spending money.