Can you buy just a wooden sofa frame?

[drspouse]

We got the DCs a play sofa (think cushions to build a fort type thing) for Christmas intending them to be the only sofa in the play room, but they are too low on their own and the existing sofa has had it. They are from here to give you an idea:

cowch.co/

Can you get just wooden sofa frames (it doesn't matter if they aren't the exact size) so we could use them on a raised frame?
I can see a few vintage ones on Ebay but other than that I'm drawing a blank. Futon frames are generally too big or too low.

I've see a hack on youtube where someone makes a corner sofa from this bed frame (two stacking frames).

www.ikea.com/gb/en/p/utaker-stackable-bed-pine-00360484/

I think it could work with what you have.

My Son has this bed in his room (but as a bed) and one of the standard mattresses is a bit wide but lays across well as only one side of each frame is raised.

Good idea!

Paletts cut to fit?