I ran millions through a title company before I retired. The issue of fund clearance was always on top of my worries. This information is a few years old, but probably still valid:
when I asked my banker when a Hong Kong check would "absolutely clear", her answer was "never, the issuing bank can always make a claim against your account and we must deduct from your account" then fight it out in Hong Kong.
I met a white faced attorney who had just dispursed millions on a closing after confirming with his bank that the funds had been wired and received. The person wiring the funds called and said it was a mistake, and his account was charged back (eventually fixed). I did not know until then that a "ACH Funds Transfer" is reversible, as opposed to an actual "Fed Wire". My banker told me to set up a separate account for all wires, to take the money out of that account as soon as it was available and put it into another bank, so that if a reversal is initiated, it is not automatic, leaving it to be sorted out by the courts but at least you don't automatically lose your money.
Banker told me that we have a treaty with Canada that , even though the check has "actually cleared" a Canadian can claim fraud up to 6 months later and my bank is obligated to reverse the funds. Sure, it can be sorted out later, (in Canada?) but what a pita.
I love using cc on purchases from venders, and it is a pita to get a postal money order. But in my opinion an individual seller can't do better=I have never heard of the PO paying then claiming it was a bad check, but I would not be surprised if there is a way.
Don't do it! 
