Still on the fence here. It reads like his English just isn't that good. On the other hand, he mentions "my claint". Now I'm assuming he meant to spell client, but is he someone that comes over from [wherever] to score deals for friends/paying clients or is he trying to say that he's getting it for a friend and doesn't know the right word in English.
Perhaps you could ask him if it worries you. Again, a bank money order is like cash. You face no risk at all as long as you cash it before you send the bag. I'm assuming you have NO RETURNS in big bold print in your information? If you DON'T then you do need to be concerned. You know the "bait & switch" technique where buyers get real designer goods, complain they are fake and RETURN a fake.
Clear these things up and you might feel better. I'm facing a similar concern on a bag I've got for sale on eBay. It's set up to accept Best Offers. I got a half decent one last night, but it's from a person with ONE feedback dating back THREE YEARS. That makes ME nervous what with so many older screen names being grabbed by scammers. Obviously, I've not committed to their offer yet either.....