In come Czekaj, Dragons pair Gareth Chapman and Chris Davies and Aled Brew (Ospreys) as regional calls and injury demand changes.
"It was a fantastic performance by the squad in Melbourne, they are raising the levels every time they compete and it would be good to finish off the season with a decent showing in Hong Kong," said Wales Sevens Head Coach Dai Rees.
"However, it is going to be tough because expectations are getting higher all the time and it will be a tall order to qualify for the top eight after the opening two days."
Wales beat South Africa 29-28 in Melbourne to take the Plate title and the two find themselves in the same Pool in Hong Kong, along with Portugal and China.
Wales Sevens: James Merriman (Gloucester Rugby), Jonathan Edwards (Llanelli Scarlets), Robin Sowden-Taylor (Cardiff Blues), Rhys Oakley (Newport Gwent Dragons), Wayne Evans (Cardiff Blues), Rhodri McAtee (Penzance), James Hook (Ospreys), Tal Selley (Llanelli Scarlets), Gareth Chapman (Newport Gwent Dragons), Chris Davies (Newport Gwent Dragons), Aled Brew (Ospreys), Chris Czekaj (Cardiff Blues)