Good question, haven't seen one of those in years. Bushflying Forum used to have a calendar on the website, not sure if they still do. I took my 520 to Johnson Creek 13 years ago and it was a blast. She performed great on the grass.
Have you joined RAF? They have a lot of little nice dirt strip flyins etc and the 520 is amazing for all that stuff, as it can get in and out anywhere.
I sometimes dream of building a carbon fibre copy of the 520 - be an amazing plane!