Are there any oddsmakers accepting bets on electors throwing their support behind Hillary?

Nope. Because it literally cannot happen. When a Democrat wins your state, you are essentially electing the Democrat electors. These are actual people that represent the Democrat party. (If a Republican wins your state, you're electing the actual individuals who ARE Republican electors.) So, the Democrat electors are not going to have a crisis of conscious and cast their vote for the Republican.

Bets on American Politics are Only made outside of the USA and since the Leaders of other Nation are clamoring to get interviews with Trump and watching the surge in the Stock Markets we can assume the only bets being made are those placed by by gambling addicts.

No.

They must like losing money.

No.

If there are, the odds would be about 200 billion to 1

Odds have nothing to do with Politics.

I suspect some odds maker is doing this; I know of none; in fact I know of no odds makers at all.