Why in the world would you suspect an engine block crack? This isn't rocket science to diagnose and I would be really, really surprised to hear of a cracked block. My first expectation: The water pump is weeping coolant because it's worn out. This can happen on any Honda engine and it means you need to change a $60 water pump and to do that, a $60 timing belt plus of course the labor to do it. It's overdue, if you haven't done it yet anyways. Let me back up....I just looked quickly and there's a full kit I see right off at Amazon for $55 that has the timing belt, water pump and tensioner. Yes, you have to provide labor but Hondas are one of the very easiest engines to learn on. My first 2 timing belts were on a 91 CRX-Si (D series single cam) and then a 91 Acura Integra (B18 dual cam) and they are so easy and straight forward, I couldn't believe it took such short time. I adjusted the valves before closing it all up because I had so much extra spare time.
It could also be any one of a number of other things. Radiators with plastic caps fail over time and this would be consistent with your description. Likely where one of the hoses is clamped on. It's not overly hard to just drain the thing and look for a crack (you also might just see where it's leaking).
As mentioned, hoses are old unless they've been replaced. Could be a $7 hose somewhere. Anyways, some non-internet diagnosis is in order before you declare that the engine block is cracked.