Remember the timing of RV sales. Summer is peak season, so people are looking to buy in March-May and looking to sell in September or later. Be patient and keep looking. Even if you don't find one in time to use it this summer, your wife can enjoy weekend trips over fall and winter and look forward to next summer. As someone else suggested, look for bus conversions. Even if you can't find one that has everything you need, you can probably come close enough to make it worth modifying. The toy hauler idea sounded promising too. I have mobility issues and have been looking for months for a motorhome that I can use. Finally found a lovely Class A last week. So don't give up!
Also, travelling in a motor home without a tow vehicle is quite manageable. That is what I did with our previous 2 motorhomes, a 29' Fleetwood and a 34' Fleetwood. We never took along a toad. Very occasionally it kept us from doing something (I chickened out of trying one steep-looking road in Yellowstone) but not often. It did require some advance planning, but OTOH it was a plus to only have to unload the groceries once. ;)