May just have to get a BD burner for this, though logistically this may be hard (no more SATA ports, and don't wanna get rid of my HD-DVD/BD combo drive).
It's a shame LG dropped HD-DVD read capability from their recent BD writers as my unit was only $85 and it otherwise would have been a good replacement for your combo drive. Wouldn't have been difficult to include it as a bonus or cost them money.
I still have my original LG BD writer that has HD-DVD read capability, but that was like $400.
You could get an enclosure for a 5" drive and connect it via usb externally, if you don't have external eSATA ports available (or even a usb->SATA converter and SATA PSU for connecting a bare drive externally when necessary).