How can I send a payment to myself with lightening to rebalance 2 channels?
First of all, there are already scripts that automate this process. Check C-Otto's rebalance script, for example.

Secondly, I wouldn't assume that finding a route via queryroute guarantees that the balances in the used channels could actually support your payment. I think it just means that the theoretical capacity in your nodes' view of the LN is sufficient. Knowing if the route actually works involves trying to route across it.

To address your concrete questions, I don't know if queryroute supports loops by now, but from glancing over the above script, it appears that it should. 

As for your 2nd question, fees are always taken by the node forwarding a payment for sending across a channel, not the recipient in a channel. So if you try to route you-bitstamp-lpu-you, there are only two forwarding hops here, bitstamp and lpu. And they will require the fees that they have announced for the channel bitstamp-lpu (announced and collected by bitstamp) and lpu-you (announced and collected by lpu).