If you are looking for one they are now known as the "Fat" version, since the slim version came out.
Not all fats have backwards compatibility, only the following models: CECHE01, CECHA01, CECHB01. The rest do not do backwards compatibility.
Good to know. I don't particularly use consoles for gaming, but I do keep my eye out at thrift stores for damaged ones to do part swapping to make working units. Done an XBOX or two and quite a few 360s, haven't started in on the playstations yet.