Here are a couple of base stands suitable for fitting to the bottom of suitcases, enabling them to stand upright. Hopefully one of them matches the one you need for your case.
SBS2
£11.40
(£9.50 ex VAT)
11.83 USD, 11.13 EUR, 85.62 CNY, 1,824.28 JPY
SBS3
£11.40
(£9.50 ex VAT)
11.83 USD, 11.13 EUR, 85.62 CNY, 1,824.28 JPY