[sfritchen1]

The serial number for the R13 I just got is 242XXX which is from the eighties. Now, I'm not sure if that is PreR13 or just a regular R13. And what is a PreR13?

 

[averageschmoe]

an instrument made before the R-13. your question would be better answered on the Buffet website as there are a few varieties of the R-13 made.

 

[clarnibass]

If it's from the 80s it is not a pre-R13 which is only a model from before R13 started which is around mid 50s. It can be (and likely is) an R13. The R13 is known for not having the model name written on the clarinet. It's unlikely, but still possible, that it is another model and the name faded away (usually engraved and doesn't fade). If it has a model name, it's not R13.