There is no vacuum port on the AQ130. As far as cold starts, there are no chokes on the Solex carbs, so yes, it will be hard to start when cold. Best thing to do is go with an electronic spark conversion kit. Hot Spark and Pertronics both make good units. Make sure your timing is set correctly and that the timing does in fact advance.
Make sure the carbs are tuned correctly. Takes a little bit of finesse, but it's not hard to set the idle mixture and idle. Then make sure that your accelerator pump linkages are set correctly. Several of the hold down bolts can be a challenge to tighten. If you need to, remove the valve cover to tighten them correctly and eliminate any vacuum leaks at the base of the carbs.
You will need to find out what your particular engine like for cold startup. Might be just one or two pumps of the throttle, and then hold it 1/3rd of the way open. Experiment with it and see what works best for your boat. At the high mountain lakes on cold mornings, I've given mine a shot or two of starting fluid. Use at your own risk, just don't over do it.
As far as parts being hard to find. Yes, it can be a bit of a challenge, but not really that hard to find normal maintenance parts. Believe me, tuneups get MUCH cheaper once you get rid of the points and condenser. Google is your friend. Even finding parts for an engine rebuild isn't that hard.
