"Cheap" and "Warwick" will never work together, unless you want one that is missing half the body and has been gutted of all hardware, frets, and electronics...
It'll take some saving, but you're much better off waiting until you can afford a decent Warwick.
Yeah, I would save up a bit more. In the long run you will be happy you did IMO. I paid about $900 or so for a used Warwick Thumb BO5 in absolute mint showroom condition with a hard case. I'm sure you could find a good deal on a decent vette.
It is an investment that should last you for years to come, so put some cash into something nice if at all possible.
I think the neck shape is different too, but I don't have enough experience with one to be sure. It was years ago that I last got to try a wenge version.