Well crap - finally got the correct choke tube only to find that the gun had been dropped which smacked the ram rod brass end on the barrel. This was because of the wrong choke in the gun - while the choke tube it came with looked like it fit, it was a slightly smaller diameter - And being dropped somehow the brass tip put a flat spot on the barrel at that spot.
This Flat Spot stopped the correct Choke tube from being screwed in the barrel. The gunsmith got it back to round but in doing so the barrel lug (which holds the barrel to the stock) was so corroded (really couldn't see that with the barrel off) broke off the barrel. Now the lug needs to be welded back on.

Always a good thing though. Had I shot it - potential to launch that barrel back at me. Someone could have gotten hurt like me.
Will need to find something else to whack ole Mr Tom.

and yes I will have that lug welded back on......
Crap

JW