As I was doing this, I had an epiphany! I had just unzipped a bed that had an egg crate mattress pad in it. The bed was one of the cheaper ones there because it was on sale for $24.99 (normally $39.99). It occurred to me when I saw that bed that I could do this myself for MUCH cheaper.
(Are you surprised that it would occur to ME to make something myself? Didn't think so.)
The bonus in making the bed for myself is that I could make TWO beds. Our other dog has a bed, but it doesn't have a removable cover & thus isn't as easily washed as I would like.
Here's what I did:
I got an egg crate mattress pad. (Like the one pictured below.) The one below cost just under $17 at Amazon. However, they have the cheaper ones for $10 at Walmart.
Picture from Amazon
I took the twin-sized pad I got & cut it in half (we have big dogs). If you were so inclined, you could sew a "real" cover to go over one of these. Instead, I chose to take the easy way out & just used a couple of old fitted sheets. I wrapped those over the beds & kept it simple. If you didn't have a couple of old sheets to use, you can usually buy a fitted sheet at a thrift store for $2.
If you had to buy a couple of fitted sheets, your total out-of-pocket would be around $15, including taxes. If you just had to buy the pad, your cost would be even lower (just over $10). Keep in mind, this is for TWO beds! That means you're total cost PER ped would be $5-$8...for a bed that costs almost $40 brand-new!
With that lower cost comes MUCH less stress should a new puppy happen to chew the bed or have an accident (our older dog will throw up if she happens to eat something that doesn't agree with her).