User blog comment:ThereonVC/Help, Australian Google play dilemma/@comment-25151790-20150515220605

You could try using a VPN to connect to a server in a country where Valkyrie Crusade is still available.

I haven't tried any Android VPNs though, so you'll have to ask others for recommendations. (User_blog:AutDawn/Guarantee_SR_ticket_from_GameDash this blog recommended the psiphon app)