I'd agree with Bob - a duet would probably be more familiar to you as an accordianist than anglo or english. I've never played accordian, but I have owned and played anglo, english, McCann and Crane duets in my time (look at my name and guess what I settled on!). My Crane is only 48 key, but I use it for song accompanyment and dance music (I have played for Morris dancers but am now in a ceilidh band). The hard part is finding one - nobody makes them for stock nowadays, so it's usually a matter of waiting for someone to die .... but it's worth it.

Andrew