Well folks, many thanks for all the advice, on and off the forum.
I can report that I did a swap + cash for my Jeffries for a 2.5 row castagnari from "charles" who emailed me from this forum post (he was the first one!). it turned out that he only lived about 10 miles from me (NW england), so we were easily able to do the deal.
I now have a new box to play, and aching arms already from the extra weight when compared to my poker work Hohner. I am enjoying it though...
Once again, many thanks for the help..