Many of the old bedspreads were waffle, very commonly in use those days, 40s+. No-one could be fussy about washing these heavy items those days and they would have been too big for a dolly tub or twin tub, they would likely have gone through a mangle after maybe one small rinse.
Weigh each one if you can ie bathroom scales when carrying. One would certainly fit in my machine and would get a relatively gentle wash as most machines have gentle drums. Just weigh and then check if its the right weight for your machine. I would use a delicate cycle with a wool wash liquid with an extra rinse and later an additional fast spin.