Found this image in a Facebook Group about FNH SCARS. The post did not have any information other than some jokes about it.

The firearm looks like a Mossberg 702 Plinkster with a tree branch whittled out to accept the Plinkster receiver. With the vertical sticks as a vertical grip and pistol grip, I can only extrapolate that this was done for a laugh. However it looks like it could be a feasible stock for a .22LR rifle.