My youngest is 16 years old, so anything we might have had has been given away ages ago. We *did* have a portable play pen that we used; also we'd gotten a 'rocking chair' -- looked like a car seat but emphatically wasn't, being lighter weight in general. This was cause he gurgled when he slept (that the doctor said ws nothing, his lungs were clear, his head was clear...) but having him sleeping slightly tilted up made it less. Supposedly one wouldn't be able to find these now, because omg someone might think it's a carseat... but it's a thought. Definitely think about repurposing other things -- as long as he'll sleep in/on them, does it matter if it was *intended* for baby to sleep on?

I thoroughly recommend *against* air mattresses, unless it's a small one just for him.