Hi,
IMHO, It doesn't matter if it's obsolete, it matters if it's available and fulfils the required function. ...And isn't overly expensive. I guess you want PDIP... Jaycar sell the XR2206, it's only $20... What about the XR2209 (8-pin version)? I recollect RS UK were selling them off at ~$6 each three years ago.
Failing that, op amps can make sine waves. Look for **broken link removed** and browse section 2 for a couple of ideas, e.g.:
View attachment 149999
There's also **broken link removed** with more pages and less pictures on each of them for some reason...It must be the modernisation process. First is National Semiconductor copy, second is TI.
This may provide some ideas, too:
AN-263 Sine Wave Generation Techniques