There is a two-keyed Grinter flute for sale in Dublin on done deal ie. €2500.
https://www.donedeal.ie/brassandwind-for-sale/grinter-flute/30595516
“Selling this flute made by the late Michael Grinter in 2002-2003. This is a two keyed flute (G# and F natural) made from Blackwood. I am selling it as unfortunately it does not get many chances to be played. It is well broken in and has been cared for. It has a lovely sweet tone. There are a few marks of wear and tear but nothing major. I will provide both hard and soft case with the flute. Price is negotiable.”