Go to the bank that you have the most money in, and ask them their rate. They might give a customer a better rate than a non-customer.
If their rate is less than $1768.56, then tell them you want them to price match for a good customer.
For such a relatively small amount 2-3% is to be expected (double that for the spread). Royal Bank has been a bit of an outlier in my experience in giving better exchange rates (I used them to get USD to import a car some years back), might be worth asking them.
That's a pretty impressive return for a few hours delay.