Do the shells for the v1 Playgo / Pocletgo 2 fit the GCW? If you're in the UK I have a one for sale with buttons etc, it's currently on eBay.
The board for this model of Playgo had GCW Zero written on it so worth checking if it's compatible as you'll probably find it easier to get a spares/repairs one of those than the GCW.
GPD Win, GPD XD 64gb, PlayGo, RS-90, 3DS XL, DSi XL, GBA SP, GBBC Clone, Gameboy Pocket c/w screen mod, PSP Go
ASUS TUF, Medion Erazer, Toshiba Z20t, Dell Mini 9, Psion 5MX, Toshiba 3480ct
Tons of other old laptops and tablets.....