Time for a New carb

I was disappointed to see my 650DP was leaking from a pin/shafts just above the mounting flange and would not idle when I fired it up after sitting for about a month. It was fine last time I parked it.

So, I'm thinking I may just go ahead and replace it, with the idea of possibly getting a little better fuel economy from a new unit. That DP really sucked the gas when I romped on it. I may also go with a 904 trans at some point, just to try out the auto trans in it, still undecided. Nothing radical on the engine basically stock, what you see on my sig, plan to stay that way.

Considering all that, what carb would you run on this engine?