There's a guren for every version.
The R1 version is available like gunpla (model kit) or action figure.
http://www.hlj.com/product/BAN953808
http://www.hlj.com/product/BAN952866
The guren kashou first half of R2, just like action figure, but high quality:
http://www.hlj.com/product/BAN956916
And about the second half R2 guren...seems it will be the last model in project, before they want build action figure for the rest of knight of round knightmares.