Embedded USB-Blaster

Not officially. But the kit schematics are distributed with all the kits so you can see how it was done. The integrated USB blaster usually uses a MaxII CPLD and an external USB chip from FTDI. It shouldn't be too hard to reverse engineer the system, IIRC it isn't complicated, but you won't get official support from Altera on this.

If memory serves, the hardware implementation is pretty straightforward, the hard part is getting the MAX II configuration file from Altera. You may have to write that code yourself but it is probably worthwhile to ask Altera, especially if you have a good relationship with your FAE.