An update that happened about an hour ago is what is happening here. They got increased from like 800gp to 75K per boot. So basically you just made 74,200 gp per boot you own.
You said you have 700 of them, you just made a lot of money. Go sell them to Tenzig for 45,000 gp each (he accepts them noted) as they aren't sell-able on the GE.