I have an old dog that had trouble getting in my SUV, so we bought one of the collapsible step ladder things.
like this:
http://www.stacksandstacks.com/html/...step-stool.htm
And they can just stash it under the bed when not in use.
(Weirdly, it also taught the dog to look for things he could use as steps in other situations rather than jumping. When he tries to get on the bed now, he now steps on the bed rail then the top. Who says you can't teach an old dog new tricks?)
If you wanted to though since it's inside, you could go with a little upholstered foot stool.
http://www.amazon.com/b?ie=UTF8&node=3733621
As your post indicates, you know they've got the ramps especially for this purpose but I think they are kind of ugly and bulky for someone to have out all the time, but maybe that's just me. You kind of have to scroll down, but this site has a lot of them:
http://www.discountramps.com/dog_ram...FQK0HgodJ2M-cw