Hopefully, someone will help you out with a replacement set of wings, however, all is not lost if not.
The 'butchered undercarriage bay' is, I assume, the integral moulded kit wheel wells being cut out? The GMF resin replacement undercarriage bay (as far as I remember) is basically a 'box' that fits over the internal wheel aperture area, so this should be recoverable.
As for the missing upper wings, I assume that this would be for for the fabric wing conversion? If so, it is onlythe upper inner section of the wings that are missing. There are two ways that you could possibly address this problem if you so wish. The first is bend a strip of 1mm or 1.5mm plastic card over a rounded surface to match the wing upper aerofoil shape and cut it to match the wing root and outer wing panel ajoining butt edges (adding internal supports and filler where necessary).
The other thing that you could try is to cleaverly cut sections of the removed lower outer wing panels so that a 'jigsaw' of parts can be glued together in such a manner as to form new upper wing inner sections - I would prefer to first route.