Replacing Vintage AS Mattresses

[obxgal]

I bought a '75 Airstream Excella 500 that had had the original mattresses taken out. It's a center-bath unit that had the curved twin beds. We're thinking of replacing the mattresses with another to fill the center so it can be dismantled into twins or kept as a queen, much like a banquette is made into a bed, with bolsters filling in the center. I'm torn as to whether to get a high-grade dense foam made up, or to contact one of the afore-mentioned "custom mattress" companies (which may be really pricey).

Any of you had experience in replacing vintage Airstream mattresses? On another forum they suggested cutting up pre-made mattresses and sewing on a support on the side where chopped (removing excess springs, etc.) They said that would be far cheaper than ordering anything custom.

I don't need it to be the best in the world...but I do like a comfy bed. :=)

Any ideas??

Susan in Va