Thanks guys.
I asked Colt's customer service 2 questions, as there's a collector here unwinding his collection and I figured I may try to pick up a few at the "right" price:
1. Was a Python 38spl ever made in 4" - all I've ever encountered is reference to the 8" 38spl "Target" model.
2. What is the serial no. cut-off for the Anaconda "problems".
The reply was: "We did make a python in just 38 special not sure what year it was manufactured, not sure what barrel length also. If you get the serial number it can be researched by our archive dept. They do have fees to research the gun."
I knew that already (in fact I know a little more about the 8" model than Colt it seems)! No, I'm not spending $75 for something I may not buy. No reference was made to the Anaconda query. Probably avoiding "liability". Anyhow, to their credit there was at least a speedy reply.
From the Taffin article I assume post 1991/2 the "problem" was likely resolved and I could try to establish that on serial number. Being out of the US and with these probably slow sellers here there's probably more chance you'll find the "bad" ones over here.
Alternatively I can buy a Mod29, of which there are a couple too, probably for less money. But then it's also not as robust as an Anaconda. I was just thinking of starting a (tiny) Colt collection. I have a SBH in .44 Mag already, but I don't like buying things that won't live up to expectations, even as "collectibles".