You should try Walmart Billpay. Much better than money orders in my opinion, just don't go over $2500 in one tranaction or they start asking for lots of info. You can only do 4 debit swipes so if they are all $500 then you can pay $1998.12 with the $1.88 fee.

I did a $2000 and a $1200 back to back last night with no problem but the cashier is very comfortable with doing these for me.