I'm kind of in the same boat in that I'm looking to get some more jets for my autolite 1100. I'll be buying a half dozen different sizes to play with. I found a place in Arizona that sells them at the following link...
http://www.swapsupply.biz/
Picking the right main jet will be based on a number of factors for your driving locations, including temperature, pressure & humidity (to a lesser degree). The autolite 1100 in my 66 Mustang (auto trans) currently has a 69F main jet installed. My plan is to borrow a wide band O2 datalogging tool to monitor the effects of different main jet sizes in conjunction with some timed runs for my location and then I'll be able to pick what best suits my application. I used to have a LM-1 wide band O2 datalogger from Innovate Motorsports and this would have been perfect for this task, but that toy is gone. It may be a while before I can borrow the right tools, but you can always use the seat-of-the-pants dyno to see which main jet gives you the best performance and then error on the rich side.
There are various reason why an engine will surge, but I corrected the surging problem I was having in our 66 Mustang by adjusting the float level to exactly 1 & 5/32". Just a 1/16" of an inch less on the float height and the car would surge, so make sure your adjustment is on the money.
If your car is hesitating off ide, then perhaps the (AP) accelerator pump is not working. It's quick and easy to check your AP. With the engine off, look into the carb's bore and quickly open the throttle all the way via the throttle linkage. You should see a stream of fuel squirt from an orifice inside the bore. If you quickly open the throttle all the way a number of times and you do not see any fuel squirting from any orifice from inside the bore, then your AP is not working (due to check ball / weight, or diaphragm, etc).
If by chance you're in North O/C SoCal, I'd be happy to help you set your float level or check out your AP if you don't know how to do it.
