Sounds like water pump to me too.

Don't waste you time/money on the pressure test. You've already mentioned that it is a 'weep' type leak and not a steady drip so the pressure test prolly won't show anything (IMHO).

Now for the big question: Is it time for a timing belt change. A lot of the work to replace the water pump is the same as for the timing belt change so it's usually recommended to do both at the same time.