LiteOn. The model name can be re-arranged to match (LTR)-52xx7S, which is what a few of LiteOn’s drives were called. There are many other OEM drives with a model number like DRW-6S160P (rewritten as SHW-160P6S, a LiteOn DVD-RW drive) where all you have to do is just rearrange a few characters and you’ll easily know.
A Google search confirms it is a LiteOn, the LTR-52327S. Which revision of the 52327S it is, I cannot say. But I know they are good drives. http://www.google.com/search?q=CDR-7S52