Yeah, but they tend to be lower efficiency (UEF 3.0) and CA rebate program requires UEF 3.3 or higher, which apparently you can only get by switching to the higher voltage.
Edit: to clarify, I was referring to the California state rebate of $700 or $900 (depending on capacity) taken off the purchase price at checkout. The federal tax credit of 30% applies to the 120V drop-in replacement as well as the 240V models.